There was considerable Axis naval activity in Australian waters during the
Second World War
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, despite
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
being remote from the main battlefronts.
German
German(s) may refer to:
* Germany, the country of the Germans and German things
**Germania (Roman era)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizenship in Germany, see also Ge ...
and
Japanese warship
A warship or combatant ship is a naval ship that is used for naval warfare. Usually they belong to the navy branch of the armed forces of a nation, though they have also been operated by individuals, cooperatives and corporations. As well as b ...
s and
submarine
A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...
s entered Australian waters between 1940 and 1945 and attacked ships, ports and other targets. Among the best-known attacks are the
sinking of HMAS ''Sydney'' by a German raider in November 1941, the
bombing of Darwin by Japanese naval aircraft in February 1942, and the Japanese
midget submarine attack on Sydney Harbour in May 1942. About 40
Allied merchant ships were
damaged or sunk off the Australian coast by
surface raiders, submarines and
mines.
Japanese submarines also
shelled three Australian ports and submarine-based aircraft flew over several
Australian capital cities.
The
Axis
An axis (: axes) may refer to:
Mathematics
*A specific line (often a directed line) that plays an important role in some contexts. In particular:
** Coordinate axis of a coordinate system
*** ''x''-axis, ''y''-axis, ''z''-axis, common names ...
threat to Australia developed gradually and until 1942 was limited to sporadic attacks by German armed merchantmen. The level of Axis naval activity peaked in the first half of 1942 when Japanese submarines conducted anti-shipping patrols off Australia's coast, and Japanese naval aviation attacked several towns in
northern Australia
The unofficial geographic term Northern Australia includes those parts of Queensland and Western Australia north of latitude 26th parallel south, 26° and all of the Northern Territory. Those local government areas of Western Australia and Q ...
. The Japanese submarine offensive against Australia was renewed in the first half of 1943 but was broken off as the Allies pushed the Japanese onto the defensive. Few Axis naval vessels operated in Australian waters in 1944 and 1945, and those that did had only a limited impact.
Due to the episodic nature of the Axis attacks and the relatively small number of ships and submarines committed, Germany and Japan were not successful in disrupting Australian shipping. While the Allies were forced to deploy substantial assets to defend shipping in Australian waters, this did not have a significant impact on the
Australian war effort or American-led operations in the
South West Pacific Area
South West Pacific Area (SWPA) was the name given to the Allied supreme military command in the South West Pacific Theatre of World War II. It was one of four major Allied commands in the Pacific War. SWPA included the Philippines, Borneo, the ...
.
Australia Station and Australian defences
The maritime approaches to Australia were designated the
Australia Station prior to the outbreak of war. This vast area consisted of the waters around Australia and eastern
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...
, and stretching south to
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...
. From east to west, it stretched from
170° east in the
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...
to
80° east in the
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...
, and from north to south it stretched from the
Equator
The equator is the circle of latitude that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern Hemispheres of Earth, hemispheres. It is an imaginary line located at 0 degrees latitude, about in circumferen ...
to the Antarctic. While the eastern half of
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...
was an Australian colonial possession during the Second World War and fell within the
Australia Station, the Japanese operations in these waters formed part of the
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...
and
Solomon Islands campaign
The Solomon Islands campaign was a major military campaign, campaign of the Pacific War during World War II. The campaign began with the Empire of Japan, Japanese seizure of several areas in the British Solomon Islands and Bougainville Island, B ...
s and were not directed at Australia.
The defence of the Australia Station was the
Royal Australian Navy
The Royal Australian Navy (RAN) is the navy, naval branch of the Australian Defence Force (ADF). The professional head of the RAN is Chief of Navy (Australia), Chief of Navy (CN) Vice admiral (Australia), Vice Admiral Mark Hammond (admiral), Ma ...
's (RAN) main concern throughout the war. Although RAN ships frequently served outside Australian waters, escort vessels and
minesweepers
A minesweeper is a small warship designed to remove or detonate naval mines. Using various mechanisms intended to counter the threat posed by naval mines, minesweepers keep waterways clear for safe shipping.
History
The earliest known usage of ...
were available to protect shipping in the Australia Station at all times. These escorts were supported by a small number of larger warships, such as
cruiser
A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several operational roles from search-and-destroy to ocean escort to sea ...
s and
armed merchant cruiser
An armed merchantman is a merchant ship equipped with guns, usually for defensive purposes, either by design or after the fact. In the days of sail, piracy and privateers, many merchantmen would be routinely armed, especially those engaging in lo ...
s, for protection against surface raiders. Important military shipping movements were escorted from the start of the war, but
convoy
A convoy is a group of vehicles, typically motor vehicles or ships, traveling together for mutual support and protection. Often, a convoy is organized with armed defensive support and can help maintain cohesion within a unit. It may also be used ...
s were not instituted in Australian waters until June 1942. The Australian naval authorities did, however, close ports to shipping at various times following real or suspected sightings of enemy warships or mines prior to June 1942.
The
Royal Australian Air Force
The Royal Australian Air Force (RAAF) is the principal Air force, aerial warfare force of Australia, a part of the Australian Defence Force (ADF) along with the Royal Australian Navy and the Australian Army. Constitutionally the Governor-Gener ...
(RAAF) was also responsible for the protection of shipping within the Australia Station. Throughout the war, RAAF aircraft escorted convoys and conducted reconnaissance and
anti-submarine patrols from bases around Australia. The main types of aircraft used for
maritime patrol
Maritime patrol or maritime reconnaissance is the task of monitoring areas of water. Generally conducted by military and law enforcement agencies, maritime patrol is usually aimed at identifying human activities.
Maritime patrol refers to active ...
were
Avro Anson
The Avro Anson is a British twin-engine, multi-role aircraft built by the aircraft manufacturer Avro. Large numbers of the type served in a variety of roles for the Royal Air Force (RAF), Fleet Air Arm (FAA), Royal Canadian Air Force (RCAF), R ...
s,
Bristol Beaufort
The Bristol Beaufort (manufacturer designation Type 152) is a British twin-engined torpedo bomber designed by the Bristol Aeroplane Company, and developed from experience gained designing and building the earlier Bristol Blenheim, Blenheim li ...
s,
Consolidated PBY Catalina
The Consolidated Model 28, more commonly known as the PBY Catalina (U.S. Navy designation), is a flying boat and amphibious aircraft designed by Consolidated Aircraft in the 1930s and 1940s. In U.S. Army service, it was designated as the OA- ...
s and
Lockheed Hudson
The Lockheed Hudson is a light bomber and coastal reconnaissance aircraft built by the American Lockheed Aircraft Corporation. It was initially put into service by the Royal Air Force shortly before the outbreak of the Second World War and ...
s. Ansons were the main type available during the first years of the war, but were not well suited to this task due to their short range and modest weapon-carrying capacity. The introduction of Beauforts and Hudsons considerably improved the RAAF's maritime patrol and anti-submarine capacities. A network of airfields along the Australian coastline was established over the course of the war to support the RAAF's maritime patrol operations. Anti-submarine work required intensive efforts by the RAAF aircrew. For instance, aircraft needed to sweep the entrance to harbours before convoys departed and then constantly patrol over them while they were at sea.
The Allied naval forces assigned to the Australia Station were considerably increased following Japan's entry into the war in December 1941 and the beginning of the
United States military
The United States Armed Forces are the Military, military forces of the United States. U.S. United States Code, federal law names six armed forces: the United States Army, Army, United States Marine Corps, Marine Corps, United States Navy, Na ...
build-up in Australia. These naval forces were supported by a large increase in the RAAF's maritime patrol force and the arrival of
United States Navy
The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...
(USN) patrol aircraft. Following the initial Japanese submarine attacks, a convoy system was instituted between Australian ports, and by the end of the war the RAAF and RAN had escorted over 1,100 convoys along the Australian coastline. As the battlefront moved to the north and attacks in Australian waters became less frequent, the number of ships and aircraft assigned to shipping protection duties within the Australia Station was considerably reduced.
In addition to the air and naval forces assigned to protect shipping in Australian waters, fixed defences were constructed to protect the major Australian ports. The
Australian Army
The Australian Army is the principal Army, land warfare force of Australia. It is a part of the Australian Defence Force (ADF), along with the Royal Australian Navy and the Royal Australian Air Force. The Army is commanded by the Chief of Army ...
was responsible for developing and manning
coastal defences
Coastal management is defence against flooding and erosion, and techniques that stop erosion to claim lands. Protection against rising sea levels in the 21st century is crucial, as sea level rise accelerates due to climate change. Changes in s ...
to protect ports from attacks by enemy surface raiders. These defences commonly consisted of a number of fixed guns defended by
anti-aircraft guns
Anti-aircraft warfare (AAW) is the counter to aerial warfare and includes "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It encompasses surface-based, subsurface ( submarine-launched), and air-bas ...
and infantry. The Army's coastal defences were considerably expanded as the threat to Australia increased between 1940 and 1942, and reached their peak in 1944. The RAN was responsible for developing and manning harbour defences in Australia's main ports. These defences consisted of fixed
anti-submarine booms and mines supported by small patrol craft, and were also greatly expanded as the threat to Australia increased. The RAN also laid defensive minefields in Australian waters from August 1941.

The cargo ships that operated in Australian waters during World War II were mostly crewed by civilians, with the Australian vessels and their crews being organised loosely as the Australian
Merchant Navy. These sailors endured considerable risks in the course of their employment. Most of the cargo ships were unarmed, though some were fitted with guns. The guns on the ships that were armed were operated by
Defensively Equipped Merchant Ship personnel provided by the RAN and members of the ship's crew. Merchant seaman received war risk bonuses that were increased over the course of the war as a result of advocacy from unions. This led to them receiving approximately equal pay and allowances to members of the RAN. A 1989 inquiry undertaken by the
Repatriation Commission found that merchant mariners were exposed to greater risks than many members of the RAN as they more frequently operated in dangerous waters and their ships were not designed to survive attacks. The support provided to civilian mariners who survived the loss of their ship during the war was also generally inferior to that provided to naval personnel.
While the naval and air forces available for the protection of shipping in Australian waters were never adequate to defeat a heavy or coordinated attack, they proved sufficient to mount defensive patrols against the sporadic and generally cautious attacks mounted by the Axis navies during the war.
1939–1941
German surface raiders in 1940
German
surface raiders operated in the western Indian Ocean in 1939 and early 1940, and began to enter Australian waters in second half of 1940. The German surface raider was the first Axis warship to operate in Australian waters during World War II.
After operating off the northern tip of
New Zealand
New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
and the South Pacific, ''Orion'' entered Australian waters in the
Coral Sea
The Coral Sea () is a marginal sea of the Pacific Ocean, South Pacific off the northeast coast of Australia, and classified as an Interim Biogeographic Regionalisation for Australia, interim Australian bioregion. The Coral Sea extends down t ...
in August 1940 and reached a point north-east of Brisbane on 11 August. She then headed east and operated off
New Caledonia
New Caledonia ( ; ) is a group of islands in the southwest Pacific Ocean, southwest of Vanuatu and east of Australia. Located from Metropolitan France, it forms a Overseas France#Sui generis collectivity, ''sui generis'' collectivity of t ...
before proceeding south into the
Tasman Sea
The Tasman Sea is a marginal sea of the South Pacific Ocean, situated between Australia and New Zealand. It measures about across and about from north to south. The sea was named after the Dutch explorer Abel Janszoon Tasman, who in 1642 wa ...
, sinking the merchant ship ''Notou'' south-west of
Noumea on 16 August and the British merchant ship ''Turakina'' in the Tasman Sea four days later. ''Orion'' sailed south-west after sinking ''Turakina'', passing south of
Tasmania
Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...
, and operated without success in the
Great Australian Bight
The Great Australian Bight is a large oceanic bight (geography), bight, or open bay, off the central and western portions of the southern Coast, coastline of mainland Australia.
There are two definitions for its extent—one by the Internation ...
in early September. ''Orion'' laid four dummy
mines off
Albany, Western Australia
Albany ( ; ) is a port city in the Great Southern region in the Australian state of Western Australia, southeast of Perth, the state capital. The city centre is at the northern edge of Princess Royal Harbour, which is a part of King G ...
on 2 September and departed to the south-west after being spotted by an Australian aircraft the next day. After unsuccessfully patrolling in the
Southern Ocean
The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the world ocean, generally taken to be south of 60th parallel south, 60° S latitude and encircling Antarctica. With a size of , it is the seco ...
, ''Orion'' sailed for the Japanese-controlled
Marshall Islands
The Marshall Islands, officially the Republic of the Marshall Islands, is an island country west of the International Date Line and north of the equator in the Micronesia region of the Northwestern Pacific Ocean.
The territory consists of 29 c ...
to refuel, arriving there on 10 October.

was the next raider to enter Australian waters. She entered the Indian Ocean from the
South Atlantic
The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for ...
in August 1940 and arrived off
Western Australia
Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...
in October. On 7 October ''Pinguin'' captured the Norwegian tanker ''Storstad'' which was sailing from
Borneo
Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...
to Melbourne. A German
prize crew
A prize crew is the selected members of a ship chosen to take over the operations of a captured ship. History
Prize crews were required to take their prize to appropriate prize courts, which would determine whether the ship's officers and crew h ...
took over ''Storstad'' and mines were transferred to her from ''Pinguin''. The two ships then sailed to the east. ''Pinguin'' laid mines off the
New South Wales
New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...
coast between
Sydney
Sydney is the capital city of the States and territories of Australia, state of New South Wales and the List of cities in Australia by population, most populous city in Australia. Located on Australia's east coast, the metropolis surrounds Syd ...
and
Newcastle
Newcastle usually refers to:
*Newcastle upon Tyne, a city and metropolitan borough in Tyne and Wear, England, United Kingdom
*Newcastle-under-Lyme, a town in Staffordshire, England, United Kingdom
*Newcastle, New South Wales, a metropolitan area ...
on the night of 28 October, with the two vessels then departing for Tasmanian waters. ''Pinguin'' laid two minefields off
Hobart
Hobart ( ) is the capital and most populous city of the island state of Tasmania, Australia. Located in Tasmania's south-east on the estuary of the River Derwent, it is the southernmost capital city in Australia. Despite containing nearly hal ...
on 31 October and 1 November, and over the period 29–31 October ''Storstad'' laid mines in
Banks Strait
The Clarke Island, also known by its Indigenous name of lungtalanana, part of the Furneaux Group, is an island in Bass Strait, south of Cape Barren Island, about off the northeast coast of Tasmania, Australia. Banks Strait separates the island ...
off the north-east corner of Tasmania and off
Wilson's Promontory and
Cape Otway on the
Victorian coast. ''Pinguin'' also laid further mines in
Spencer Gulf off
Adelaide
Adelaide ( , ; ) is the list of Australian capital cities, capital and most populous city of South Australia, as well as the list of cities in Australia by population, fifth-most populous city in Australia. The name "Adelaide" may refer to ei ...
in
South Australia
South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. With a total land area of , it is the fourth-largest of Australia's states and territories by area, which in ...
in the first week of November. The two ships then sailed west for the Indian Ocean. ''Pinguin'' and ''Storstad'' were not detected during their operations off Australia's eastern and southern coasts. Mines laid by ''Storstad'' sank the cargo ship
''Cambridge'' off Wilsons Promontory and the American
''City of Rayville'' off Cape Otway on 8 and 9 November, and the mines laid off Sydney by ''Pinguin'' sank the coastal steamer
''Nimbin''. The British steamer
''Hertford'' was also damaged after striking a mine at the entrance to Spencer Gulf. ''Pinguin'' sank another three merchant ships in the Indian Ocean during November.
On 7 December 1940, the German raiders ''Orion'' and arrived off the Australian protectorate of Nauru. During the next 48 hours, they
sank four merchant ships. Heavily loaded with survivors from their victims, the raiders departed for
Emirau Island where they unloaded the prisoners. After an unsuccessful attempt to lay mines off
Rabaul
Rabaul () is a township in the East New Britain province of Papua New Guinea, on the island of New Britain. It lies about to the east of the island of New Guinea. Rabaul was the provincial capital and most important settlement in the province ...
on 24 December, ''Komet'' made a second attack on Nauru on 27 December and shelled the island's
phosphate
Phosphates are the naturally occurring form of the element phosphorus.
In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthop ...
plant and dock facilities. This was the last Axis naval attack in Australian waters until November 1941.
The raid on Nauru led to serious concerns in Australia about the supply of phosphates from there and nearby
Ocean Island, though the lack of availability of warships allowed only limited response to threats to the isolated islands. Some warships were redeployed, and it was decided to install six-inch naval guns on the islands despite provisions of the mandate prohibiting fortifications. Due to shortages of these guns the intended defences were reduced to two
field gun
A field gun is a field artillery piece. Originally the term referred to smaller guns that could accompany a field army on the march, that when in combat could be moved about the battlefield in response to changing circumstances (field artillery ...
s for each island. The most serious effect of the raid was the fall in phosphate output, though decisions made as early as 1938 to increase stockpiles of raw rock in Australia mitigated the decline. Another consequence was the institution of the first Trans-Tasman commercial convoys, with Convoy VK.1 composed of , ,
''Empress of Russia'', and
''Maunganui'' leaving Sydney 30 December 1940 for
Auckland
Auckland ( ; ) is a large metropolitan city in the North Island of New Zealand. It has an urban population of about It is located in the greater Auckland Region, the area governed by Auckland Council, which includes outlying rural areas and ...
escorted by the
light cruiser
A light cruiser is a type of small or medium-sized warship. The term is a shortening of the phrase "light armored cruiser", describing a small ship that carried armor in the same way as an armored cruiser: a protective belt and deck. Prior to thi ...
.
German surface raiders in 1941
Following the raids on Nauru, ''Komet'' and ''Orion'' sailed for the Indian Ocean, passing through the Southern Ocean well to the south of Australia in February and March 1941 respectively. ''Komet'' re-entered the Australia Station in April en route to New Zealand, and sailed east through the southern extreme of the Australia Station in August. Until November, the only casualties from Axis ships on the Australia Station in 1941 were caused by mines laid by ''Pinguin'' in 1940. The small trawler ''Millimumul'' was sunk with the loss of seven lives after striking a mine off the New South Wales coast on 26 March 1941, and two
ratings from a
mine disposal party were killed while attempting to defuse a mine which had washed ashore in South Australia on 14 July.
On 19 November 1941, the Australian light cruiser —which had been highly successful in the
Battle of the Mediterranean
The Battle of the Mediterranean was the name given to the naval campaign fought in the Mediterranean Sea during World War II, from 10 June 1940 to 2 May 1945.
For the most part, the campaign was fought between the Kingdom of Italy, Italian Reg ...
—encountered the disguised German raider , approximately south west of
Carnarvon, Western Australia
Carnarvon ( ) is a coastal town situated approximately north of Perth, in Western Australia. It lies at the mouth of the Gascoyne River on the Indian Ocean. The Shark Bay World Heritage Site, world heritage area lies to the south of the town an ...
. ''Sydney'' intercepted ''Kormoran'' and demanded that she prove her assumed identity as the Dutch freighter ''Straat Malakka''. During the interception, ''Sydney''s captain brought his ship dangerously close to ''Kormoran''. As a result, when ''Kormoran'' was unable to prove her identity and avoid a battle she had little hope of surviving, the raider was able to use all her weaponry against ''Sydney''.
In the resulting battle, ''Kormoran'' and ''Sydney'' were both crippled, with ''Sydney'' sinking with the loss of all her 645 crew and 78 of ''Kormoran''s crew being either killed in the battle or dying before they could be rescued by passing ships.
''Kormoran'' was the only Axis ship to conduct attacks in Australian waters during 1941 and the last Axis surface raider to enter Australian waters until 1943. There is no evidence to support claims that a
Japanese submarine participated in the sinking of HMAS ''Sydney''. The only German ship to enter the Australia Station during 1942 was the
blockade runner
A blockade runner is a merchant vessel used for evading a naval blockade of a port or strait. It is usually light and fast, using stealth and speed rather than confronting the blockaders in order to break the blockade. Blockade runners usua ...
and supply ship ''Ramses'', which was sunk by the light cruisers and
HNLMS ''Jacob van Heemskerk'' on 26 November, shortly after ''Ramses'' left
Batavia in the Japanese-occupied
Dutch East Indies
The Dutch East Indies, also known as the Netherlands East Indies (; ), was a Dutch Empire, Dutch colony with territory mostly comprising the modern state of Indonesia, which Proclamation of Indonesian Independence, declared independence on 17 Au ...
bound for
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
. All of ''Ramses'' crew survived the sinking and were taken prisoner.
1942

The naval threat to Australia increased dramatically following the outbreak of war in the Pacific. During the first half of 1942, the Japanese mounted a sustained campaign in Australian waters, with Japanese submarines attacking shipping and
aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering carrier-based aircraft, shipborne aircraft. Typically it is the ...
s conducting a devastating attack on the strategic port of
Darwin. In response to these attacks the Allies increased the resources allocated to protecting shipping in Australian waters.
Initial Japanese submarine patrols (January–March 1942)
The first Japanese submarines to enter Australian waters were , , and , from the Imperial Japanese Navy's (IJN's) Submarine Squadron 6. Acting in support of the Japanese conquest of the Netherlands East Indies, these boats laid minefields in the approaches to Darwin and in the
Torres Strait
The Torres Strait (), also known as Zenadh Kes ( Kalaw Lagaw Ya#Phonology 2, �zen̪ad̪ kes, is a strait between Australia and the Melanesian island of New Guinea. It is wide at its narrowest extent. To the south is Cape York Peninsula, ...
between 12 and 18 January 1942. The mines did not sink or damage any Allied ships.
After completing their mine laying missions the four submarines took station off Darwin to provide the Japanese fleet with warning of Allied naval movements. On 20 January the Australian
''Bathurst''-class corvette
A corvette is a small warship. It is traditionally the smallest class of vessel considered to be a proper (or " rated") warship. The warship class above the corvette is that of the frigate, while the class below was historically that of the sloo ...
s , and sank ''I-124'' near Darwin. This is the only full-sized submarine that was confirmed to have been sunk by the RAN in Australian waters during World War II. Being the first accessible ocean-going IJN submarine lost after the
attack on Pearl Harbor
The attack on Pearl HarborAlso known as the Battle of Pearl Harbor was a surprise military strike by the Empire of Japan on the United States Pacific Fleet at Naval Station Pearl Harbor, its naval base at Pearl Harbor on Oahu, Territory of ...
, USN divers attempted to enter ''I-124'' in order to obtain its code books, but were unsuccessful.
Following the conquest of the western Pacific the Japanese made a number of reconnaissance patrols into Australian waters. The submarines (, and ) operated off Western Australia in March 1942, sinking the merchant ships ''Parigi'' and ''Siantar'' on 1 and 3 March respectively. In addition, conducted a reconnaissance patrol down the Australian east coast in February and March. During this patrol
Nobuo Fujita from the ''I-25'' flew a
Yokosuka E14Y1
floatplane
A floatplane is a type of seaplane with one or more slender floats mounted under the fuselage to provide buoyancy. By contrast, a flying boat uses its fuselage for buoyancy. Either type of seaplane may also have landing gear suitable for land, ...
over Sydney (17 February),
Melbourne
Melbourne ( , ; Boonwurrung language, Boonwurrung/ or ) is the List of Australian capital cities, capital and List of cities in Australia by population, most populous city of the States and territories of Australia, Australian state of Victori ...
(26 February) and Hobart (1 March). Following these reconnaissance operations, ''I-25'' sailed for New Zealand and conducted overflights of
Wellington
Wellington is the capital city of New Zealand. It is located at the south-western tip of the North Island, between Cook Strait and the Remutaka Range. Wellington is the third-largest city in New Zealand (second largest in the North Island ...
and Auckland on 8 and 13 March respectively.
Japanese naval aviation attacks (February 1942 – November 1943)
The bombing of Darwin on 19 February 1942, was the heaviest single attack by the IJN against mainland Australia. On 19 February, four Japanese aircraft carriers (, , and ) launched a total of 188 aircraft from a position in the
Timor Sea
The Timor Sea (, , or ) is a relatively shallow sea in the Indian Ocean bounded to the north by the island of Timor with Timor-Leste to the north, Indonesia to the northwest, Arafura Sea to the east, and to the south by Australia. The Sunda Tr ...
. The carriers were escorted by four cruisers and nine destroyers. The naval aircraft inflicted heavy damage on Darwin and sank nine ships. A raid conducted by 54 land-based bombers later the same day caused further damage to the town and
RAAF Base Darwin
RAAF Base Darwin is a Royal Australian Air Force (RAAF) military air base located in the city of Darwin, in the Northern Territory, Australia. The base shares its runway with Darwin International Airport, for civil aviation purposes. The h ...
and the destruction of 20 Allied military aircraft. Allied casualties were 236 killed and between 300 and 400 wounded, the majority of whom were non-Australian Allied sailors. Four Japanese aircraft were confirmed to have been destroyed by Darwin's defenders.
The bombing of Darwin was the first of many
Japanese naval aviation attacks against targets in Australia. The carriers , and —which escorted the invasion force dispatched against
Port Moresby
(; Tok Pisin: ''Pot Mosbi''), also referred to as Pom City or simply Moresby, is the capital and largest city of Papua New Guinea. It is one of the largest cities in the southwestern Pacific (along with Jayapura) outside of Australia and New ...
in May 1942—had the secondary role of attacking Allied bases in northern Queensland once Port Moresby was secured. These attacks did not occur, however, as the landings at Port Moresby were cancelled when the Japanese carrier force was mauled in the
Battle of the Coral Sea
The Battle of the Coral Sea, from 4 to 8 May 1942, was a major naval battle between the Imperial Japanese Navy (IJN) and naval and air forces of the United States and Australia. Taking place in the Pacific Theatre of World War II, the battle ...
.
Japanese aircraft made almost 100 raids, most of them small, against
northern Australia
The unofficial geographic term Northern Australia includes those parts of Queensland and Western Australia north of latitude 26th parallel south, 26° and all of the Northern Territory. Those local government areas of Western Australia and Q ...
during 1942 and 1943. Land-based IJN aircraft took part in many of the 63 raids on Darwin which followed the initial attack. The town of
Broome, Western Australia
Broome, also known as Rubibi by the Yawuru, Yawuru people, is a coastal Pearl hunting, pearling and tourist town in the Kimberley (Western Australia), Kimberley region of Western Australia, north of Perth. The town recorded a population of 14,6 ...
experienced a devastating attack by IJN fighters on 3 March 1942, in which at least 88 people were killed. Long-range
seaplanes
A seaplane is a powered fixed-wing aircraft capable of taking off and landing (alighting) on water.Gunston, "The Cambridge Aerospace Dictionary", 2009. Seaplanes are usually divided into two categories based on their technological characterist ...
operating from bases in the
Solomon Islands
Solomon Islands, also known simply as the Solomons,John Prados, ''Islands of Destiny'', Dutton Caliber, 2012, p,20 and passim is an island country consisting of six major islands and over 1000 smaller islands in Melanesia, part of Oceania, t ...
made a number of small attacks on towns in
Queensland
Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...
.
Japanese naval aircraft operating from land bases also harassed coastal shipping in Australia's northern waters during 1942 and 1943. On 15 December 1942, four sailors were killed when the merchant ship ''Period'' was attacked off Cape Wessel in the Northern Territory. The small general purpose vessel was sunk by a Japanese floatplane near the
Wessel Islands on 22 January 1943 with the loss of nine sailors and civilians. Another civilian sailor was killed when the merchant ship ''Islander'' was attacked by a floatplane during May 1943.
Attacks on Sydney and Newcastle (May–June 1942)
In March 1942, the Japanese military adopted a strategy of isolating Australia from the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
, which involved capturing Port Moresby in New Guinea, the Solomon Islands,
Fiji
Fiji, officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consists of an archipelago of more than 330 islands—of which about ...
,
Samoa
Samoa, officially the Independent State of Samoa and known until 1997 as Western Samoa, is an island country in Polynesia, part of Oceania, in the South Pacific Ocean. It consists of two main islands (Savai'i and Upolu), two smaller, inhabited ...
and New Caledonia. This plan was frustrated by the Japanese defeat in the Battle of the Coral Sea and was postponed indefinitely after the
Battle of Midway
The Battle of Midway was a major naval battle in the Pacific Ocean theater of World War II, Pacific Theater of World War II that took place on 4–7 June 1942, six months after Japan's attack on Pearl Harbor and one month after the Battle of t ...
.
On 27 April 1942, the submarines and left the major Japanese naval base at
Truk Lagoon in the Japanese territory of the
Caroline Islands
The Caroline Islands (or the Carolines) are a widely scattered archipelago of tiny islands in the western Pacific Ocean, to the north of New Guinea. Politically, they are divided between the Federated States of Micronesia (FSM) in the cen ...
to conduct reconnaissance patrols of Allied ports in the
South Pacific. The goal of these patrols was to find a suitable target for a force of
midget submarine
A midget submarine is any submarine under 150 tons, typically operated by a crew of one or two but sometimes up to six or nine, with little or no on-board living accommodation. They normally work with mother ships, from which they are launched an ...
s, designated the Eastern Detachment of the Second Special Attack Flotilla, which was available in the Pacific. ''I-29'' entered Australian waters in May and made an unsuccessful attack on the neutral
Soviet
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
freighter ''Wellen'' off Newcastle on 16 May. ''I-29''s floatplane overflew Sydney on 23 May 1942, finding a large number of major Allied warships in
Sydney Harbour
Port Jackson, commonly known as Sydney Harbour, is a ria, natural harbour on the east coast of Australia, around which Sydney was built. It consists of the waters of Sydney Harbour, Middle Harbour, North Harbour and the Lane Cove River, Lane ...
. ''I-21'' reconnoitred
Suva
Suva (, ) is the Capital city, capital and the most populous city of Fiji. It is the home of the country's largest metropolitan area and serves as its major port. The city is located on the southeast coast of the island of Viti Levu, in Rew ...
in Fiji and Auckland in New Zealand in late May and did not find worthwhile concentrations of shipping in either port.
On 18 May, the Eastern Detachment of the Second Special Attack Flotilla left Truk Lagoon under the command of Captain
Hankyu Sasaki
Hankyu Sasaki (佐々木 半九, 1 January 1896 – 6 October 1971) was an Imperial Japanese Navy admiral. During World War II he was force commander of the midget submarines that attacked Pearl Harbor and Attack on Sydney Harbour, Sydney Harbour. ...
. Sasaki's force comprised , and . Each submarine was carrying a midget submarine. After the intelligence gathered by ''I-21'' and ''I-29'' was assessed, the three submarines were ordered on 24 May to attack Sydney. The three submarines of the Eastern Detachment rendezvoused with ''I-21'' and ''I-29'' off Sydney on 29 May. In the early hours of 30 May, ''I-21''s floatplane conducted a reconnaissance flight over Sydney Harbour that confirmed the concentration of Allied shipping sighted by ''I-29''s floatplane was still present and remained a worthwhile target.

On the night of 31 May, three midget submarines were launched from the Japanese force outside the
Sydney Heads
The Sydney Heads (also simply known as the Heads) are a series of headlands that form the wide entrance to Sydney Harbour in Sydney, New South Wales, Australia. North Head and Quarantine Head are to the north; South Head and Dunbar Head are to ...
. Two of the submarines (Midget No. 22 and Midget A, also known as Midget 24) successfully penetrated the incomplete
Sydney Harbour defences. Only Midget A actually attacked Allied shipping in the harbour, firing two torpedoes at the American
heavy cruiser
A heavy cruiser was a type of cruiser, a naval warship designed for long range and high speed, armed generally with naval guns of roughly 203 mm (8 inches) in calibre, whose design parameters were dictated by the Washington Naval Treat ...
. These torpedoes missed ''Chicago'' but sank the
depot ship , killing 21 seamen on board, and seriously damaged the Dutch submarine . All of the Japanese midget submarines were lost. Midget No. 22 and Midget No. 27 were destroyed by the Australian defenders and Midget A was scuttled by her crew after leaving the harbour.
Following this raid, the Japanese submarine force operated off Sydney and Newcastle and sank the coaster ''
Iron Chieftain'' near Sydney on 3 June. On the night of 8 June, ''I-24'' bombarded the eastern suburbs of Sydney and ''I-21''
shelled Newcastle.
Fort Scratchley at Newcastle returned fire, but did not hit ''I-21''. These bombardments did not cause any casualties or serious damage, but generated concern over further attacks against the east coast. Following the attacks on shipping in the Sydney region, the RAN instituted convoys between Brisbane and Adelaide. All ships of over and with speeds of less than were required to sail in convoy when travelling between cities on the east coast. The Japanese submarine force left Australian waters in late June 1942 having sunk a further two merchant ships. The small number of sinkings achieved by the five Japanese submarines sent against the Australian east coast in May and June represented a poor return for the commitment of so many submarines.
Further Japanese submarine patrols (July–August 1942)
The Australian authorities received only a brief break in the submarine threat. In July 1942, three submarines (, and ) from Submarine Squadron 3 commenced operations off the East Coast. These submarines sank five ships (including the small fishing trawler
''Dureenbee'') and damaged several others during July and August. In addition, conducted a patrol off the southern coast of Australia while en route from New Caledonia to
Penang
Penang is a Malaysian state located on the northwest coast of Peninsular Malaysia along the Strait of Malacca. It has two parts: Penang Island, where the capital city, George Town, is located, and Seberang Perai on the Malay Peninsula. Th ...
, though it did not sink any ships in this area. Following the withdrawal of this force in August, no further submarine attacks were made against Australia until January 1943.
Japanese submarines sank 17 ships in Australian waters in 1942, 14 of which were near the Australian coast. This offensive did not have a serious impact on the Allied war effort in the
South West Pacific
Oceania ( , ) is a region, geographical region including Australasia, Melanesia, Micronesia, and Polynesia. Outside of the English-speaking world, Oceania is generally considered a continent, while Mainland Australia is regarded as its co ...
or the Australian economy. Nevertheless, by forcing ships sailing along the east coast to travel in convoy the Japanese submarines reduced the efficiency of Australian coastal shipping. This translated into between 7.5% and 22% less tonnage being transported between Australian ports each month (no accurate figures are available and the estimated figure varied between months). The convoys were effective with no ship travelling as part of a convoy being sunk in Australian waters during 1942.
1943
East coast submarine patrols (January–June 1943)
Japanese submarine operations against Australia in 1943 began when and ''I-21'' sailed from Rabaul on 7 January to reconnoitre the Nouméa and Sydney areas respectively. ''I-21'' arrived off New South Wales just over a week later. It operated along the east coast until late February, sinking six ships. This was the most successful submarine patrol conducted in Australian waters during World War II. ''I-21''s floatplane conducted a successful reconnaissance of Sydney Harbour on 19 February.
and entered Australian waters in March. ''I-6'' laid nine German-supplied acoustic mines in the approaches to Brisbane. This minefield was discovered by the
sloop and neutralised before any ships were sunk. Although ''I-6'' returned to Rabaul after laying her mines, the Japanese submarine force in Australian waters was expanded in April when ''I-11'', , and of Submarine Squadron 3 arrived off the east coast and joined ''I-26''. This force sought to attack reinforcement and supply convoys travelling between Australia and New Guinea.
As the Japanese force was too small to cut off all traffic between Australia and New Guinea, the squadron commander widely dispersed his submarines between the Torres Strait and Wilson's Promontory with the goal of tying down as many Allied ships and aircraft as possible. This offensive continued until June, and the five Japanese submarines sank nine ships and damaged several others. In contrast to 1942, five of the ships sunk off the Australian east coast were travelling in escorted convoys at the time they were attacked. The convoy escorts did not detect any submarines before they launched their attacks or succeed in counter-attacking these submarines. The last attack by a Japanese submarine off the east coast of Australia was made by ''I-174'' on 16 June 1943 when she sank the merchant ship ''Portmar'' and damaged U.S.
Landing Ship Tank ''LST-469'' as they were travelling in
Convoy GP55 off the New South Wales north coast. The historian Geoff Crowhurst believes that RAAF aircraft searching for ''
I-174'' probably sank ''
I-178'' during the early hours of 18 June, but the cause of this submarine's loss during a patrol off eastern Australia has not been confirmed.

The single greatest loss of life resulting from a submarine attack in Australian waters occurred in the early hours of 14 May when ''I-177'' torpedoed and sank the Australian
hospital ship
A hospital ship is a ship designated for primary function as a floating healthcare, medical treatment facility or hospital. Most are operated by the military forces (mostly navy, navies) of various countries, as they are intended to be used in or ...
off
Point Lookout, Queensland. After being hit by a single torpedo, ''Centaur'' sank in less than three minutes with the loss of 268 lives. While hospital ships were legally protected against attack under the terms of the
Geneva Conventions
upright=1.15, The original document in single pages, 1864
The Geneva Conventions are international humanitarian laws consisting of four treaties and three additional protocols that establish international legal standards for humanitarian t ...
, it is unclear whether
Commander
Commander (commonly abbreviated as Cmdr.) is a common naval officer rank as well as a job title in many army, armies. Commander is also used as a rank or title in other formal organizations, including several police forces. In several countri ...
Hajime Nakagawa of ''I-177'' was aware that ''Centaur'' was a hospital ship. She was clearly marked with a
red cross
The organized International Red Cross and Red Crescent Movement is a Humanitarianism, humanitarian movement with approximately 16million volunteering, volunteers, members, and staff worldwide. It was founded to protect human life and health, to ...
and was fully illuminated, but the light conditions at the time may have resulted in Nakagawa not being aware of ''Centaur''s status, making her sinking a tragic accident. Nakagawa had a poor record as a submarine captain and was later convicted of machine gunning the survivors of a British merchant ship, , in the Indian Ocean, so it is probable that the sinking of ''Centaur'' was due to either Nakagawa's incompetence or indifference to the laws of warfare. The attack on ''Centaur'' sparked widespread public outrage in Australia.
The Japanese submarine offensive against Australia was broken off in July when the submarines were redeployed to counter Allied offensives
elsewhere in the Pacific. The last two Japanese submarines to be dispatched against the Australian east coast, ''I-177'' and ''I-180'', were redirected to the central Solomon Islands shortly before they would have arrived off Australia in July. The Australian naval authorities were concerned about a resumption of attacks and maintained the coastal convoy system until late 1943 when it was clear that the threat had passed. Coastal convoys in waters south of Newcastle ceased on 7 December and convoys off the north-east coast and between Australia and New Guinea were abolished in February and March 1944 respectively.
Shelling of Port Gregory (January 1943)
Only a single Japanese submarine was dispatched against the Australian west coast during the first half of 1943. On 21 January, left her base at
Surabaya
Surabaya is the capital city of East Java Provinces of Indonesia, province and the List of Indonesian cities by population, second-largest city in Indonesia, after Jakarta. Located on the northeastern corner of Java island, on the Madura Strai ...
in Japanese-occupied
Java
Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...
, destined for Western Australia. The submarineunder
Lieutenant Commander Kennosuke Torisuwas tasked with creating a diversion to assist
the evacuation of Japanese forces from
Guadalcanal
Guadalcanal (; indigenous name: ''Isatabu'') is the principal island in Guadalcanal Province of Solomon Islands, located in the southwestern Pacific Ocean, northeast of Australia. It is the largest island in the Solomons by area and the second- ...
following their defeat there. Another submarinehad undertaken a diversionary bombardment of the
Cocos (Keeling) Islands
The Cocos (Keeling) Islands (), officially the Territory of Cocos (Keeling) Islands (; ), are an Australian external territory in the Indian Ocean, comprising a small archipelago approximately midway between Australia and Sri Lanka and rel ...
on 25 December 1942.
After a six-day voyage southward, ''I-165'' reached
Geraldton
Geraldton (Wajarri language, Wajarri: ''Jambinu'', Wilunyu language, Wilunyu: ''Jambinbirri'') is a coastal city in the Mid West (Western Australia), Mid West region of Western Australia, north of the state capital, Perth.
As of the , Geraldt ...
on 27 January. Torisu sighted what he believed were lights from aircraft or a
destroyer
In naval terminology, a destroyer is a fast, maneuverable, long-endurance warship intended to escort
larger vessels in a fleet, convoy, or carrier battle group and defend them against a wide range of general threats. They were conceived i ...
near the town and broke off his attack. ''I-165'' instead headed north for
Port Gregory a former whaling, lead and salt port. At around midnight on 28 January, the submarine's crew fired 10 rounds from her
deck gun
A deck gun is a type of naval artillery mounted on the deck of a submarine. Most submarine deck guns were open, with or without a shield; however, a few larger submarines placed these guns in a turret.
The main deck gun was a dual-purpose w ...
at the town. The shells appear to have completely missed Port Gregory and did not result in any damage or casualties and the raid initially went unnoticed. While gunfire was sighted by nearby
coastwatchers, Allied naval authorities only learned of the attack when Torisu's battle report radio signal was intercepted and decoded a week later. As a result, the attack did not divert attention away from Guadalcanal.
''I-165'' returned twice to Australian waters. In September 1943, she made an uneventful reconnaissance of the north west coast. ''I-165'' conducted another reconnaissance patrol off north western Australian between 31 May and 5 July 1944. This was the last time a Japanese submarine entered Australian waters.
German raider ''Michel'' (June 1943)
was the final German surface raider to enter Australian waters and the Pacific. ''Michel'' departed from
Yokohama, Japan
is the second-largest city in Japan by population as well as by area, and the country's most populous municipality. It is the capital and most populous city in Kanagawa Prefecture, with a population of 3.7 million in 2023. It lies on Tokyo B ...
, on her second raiding cruise on 21 May 1943 and entered the Indian Ocean in June. On 15 June she sank the Norwegian tanker ''Høegh Silverdawn'' about west-north-west of Fremantle while she was sailing from that port to
Abadan, Iran
Abadan (; ) is a city in the Central District (Abadan County), Central District of Abadan County, Khuzestan province, Khuzestan province, Iran, serving as capital of both the county and the district. The city is in the southwest of the coun ...
. ''Michel'' followed up this success two days later by sinking a second Norwegian tanker, the ''Ferncastle'', in the same area. ''Ferncastle'' was sailing from Esperance to the
Persian Gulf
The Persian Gulf, sometimes called the Arabian Gulf, is a Mediterranean seas, mediterranean sea in West Asia. The body of water is an extension of the Arabian Sea and the larger Indian Ocean located between Iran and the Arabian Peninsula.Un ...
. Following these sinkings ''Michel'' sailed well to the south of Australia and New Zealand and stayed in high latitudes until she was off the coast of Chile. On 11 September, she sank the tanker ''India'' west of
Easter Island
Easter Island (, ; , ) is an island and special territory of Chile in the southeastern Pacific Ocean, at the southeasternmost point of the Polynesian Triangle in Oceania. The island is renowned for its nearly 1,000 extant monumental statues, ...
.
1944–1945
Landing in the Kimberley (January 1944)
While the Japanese government never adopted
proposals to invade Australia, a single reconnaissance landing was made on the Australian mainland. Between 17 and 20 January 1944, members of a Japanese intelligence unit named ''Matsu Kikan'' ("Pine Tree Organisation") made a reconnaissance mission to a sparsely populated area on the far north coast of the
Kimberley region of Western Australia. The unit, operating from
Kupang
Kupang (, ), formerly known as Koepang, is the capital of the Indonesian province of East Nusa Tenggara. At the 2020 Indonesian census, 2020 Census, it had a population of 442,758;Badan Pusat Statistik, Jakarta, 2021. the official estimate as o ...
,
West Timor, used a converted civilian vessel called ''Hiyoshi Maru'' and posed as a fishing crew. The mission was led by Lieutenant Susuhiko Mizuno of the
Japanese Army and included another three Japanese army personnel, six Japanese naval personnel and ten young men from Timor. Their orders, from the
19th Army headquarters at
Ambon, were to verify reports that the USN was building a base in the area. The ''Matsu Kikan'' personnel were also ordered to collect information which would assist any
covert reconnaissance or
raiding missions on the Australian mainland. They reportedly explored onshore for about two hours, and some members of the mission filmed the area using an
8 mm camera. The ''Matsu Kikan'' personnel spent the night on the boat and reconnoitred the area again the following day, before returning to
Kupang
Kupang (, ), formerly known as Koepang, is the capital of the Indonesian province of East Nusa Tenggara. At the 2020 Indonesian census, 2020 Census, it had a population of 442,758;Badan Pusat Statistik, Jakarta, 2021. the official estimate as o ...
. The Japanese did not sight any people or signs of recent human activity and little of military significance was learnt from the mission.
Japanese operations in the Indian Ocean (March 1944)

In February 1944, the
Japanese Combined Fleet withdrew from its base at
Truk and was divided between
Palau
Palau, officially the Republic of Palau, is an island country in the Micronesia subregion of Oceania in the western Pacific Ocean. The Republic of Palau consists of approximately 340 islands and is the western part of the Caroline Islands ...
and
Singapore
Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...
. The appearance of a powerful Japanese force at Singapore concerned the Allies, as it was feared that it could potentially conduct raids in the Indian Ocean and against Western Australia.
On 1 March, a Japanese squadron led by the heavy cruiser and consisting of the heavy cruisers and under
Vice Admiral
Vice admiral is a senior naval flag officer rank, usually equivalent to lieutenant general and air marshal. A vice admiral is typically senior to a rear admiral and junior to an admiral.
Australia
In the Royal Australian Navy, the rank of Vice ...
Naomasa Sakonju
was a vice admiral in the Imperial Japanese Navy during World War II and a convicted war criminal.
Biography
A native of Kagoshima Prefecture, Sakonju was a graduate of the 40th class of the Imperial Japanese Navy Academy in 1912, placing 98th i ...
sortied from the
Sunda Strait
The Sunda Strait () is the strait between the Indonesian islands of Java island, Java and Sumatra. It connects the Java Sea with the Indian Ocean.
Etymology
The strait takes its name from the Sunda Kingdom, which ruled the western portion of Ja ...
to
attack Allied shipping sailing on the main route between
Aden
Aden () is a port city located in Yemen in the southern part of the Arabian peninsula, on the north coast of the Gulf of Aden, positioned near the eastern approach to the Red Sea. It is situated approximately 170 km (110 mi) east of ...
and Fremantle. The only Allied ship this squadron encountered was the British steamer ''Behar'', which was sunk midway between
Ceylon
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...
and
Fremantle
Fremantle () () is a port city in Western Australia located at the mouth of the Swan River (Western Australia), Swan River in the metropolitan area of Perth, the state capital. Fremantle Harbour serves as the port of Perth. The Western Australi ...
on 9 March. Following this attack the squadron broke off its mission and returned to Batavia as it was feared that Allied ships responding to ''Behar's'' distress signal posed an unacceptable risk. While 102 survivors from ''Behar'' were rescued by ''Tone'', 82 of these prisoners were murdered after the cruiser arrived in Batavia on 16 March. Following the war Sakonju was executed for
war crime
A war crime is a violation of the laws of war that gives rise to individual criminal responsibility for actions by combatants in action, such as intentionally killing civilians or intentionally killing prisoners of war, torture, taking hostage ...
s which included the killing of these prisoners, while the former commander of ''Tone'',
Captain
Captain is a title, an appellative for the commanding officer of a military unit; the supreme leader or highest rank officer of a navy ship, merchant ship, aeroplane, spacecraft, or other vessel; or the commander of a port, fire or police depa ...
Haruo Mayazumi, was sentenced to seven years imprisonment. This sortie was the last raid by Axis surface ships against the Allied lines of communication in the Indian Ocean, or elsewhere, during World War II.
While the Japanese raid into the Indian Ocean was not successful, associated Japanese shipping movements
provoked a major Allied response. In early March 1944, Allied intelligence reported that two
battleship
A battleship is a large, heavily naval armour, armored warship with a main battery consisting of large naval gun, guns, designed to serve as a capital ship. From their advent in the late 1880s, battleships were among the largest and most form ...
s escorted by destroyers had left Singapore in the direction of Surabaya and an American submarine made radar contact with two large Japanese ships in the
Lombok Strait
The Lombok Strait () is a strait of the Bali Sea connecting to the Indian Ocean, and is located between the islands of Bali and Lombok in Indonesia. The Gili Islands are on the Lombok side.
Its narrowest point is at its southern opening, with a ...
. The Australian Chiefs of Staff Committee reported to the Government on 8 March that there was a possibility that these ships could have entered the Indian Ocean to attack Fremantle. In response to this report, all ground and naval defences at Fremantle were fully activated, all shipping was ordered to leave Fremantle and several RAAF squadrons were redeployed to bases in Western Australia.
This alert proved to be a false alarm. The Japanese ships detected in the Lombok Strait were actually the light cruisers and which were covering the return of the surface raiding force from the central Indian Ocean. The alert was lifted at Fremantle on 13 March and the RAAF squadrons began returning to their bases in eastern and northern Australia on 20 March.
The German submarine offensive (September 1944 – January 1945)
On 14 September 1944, the commander of the ''Kriegsmarine''—
''Großadmiral'' (Grand Admiral)
Karl Dönitz
Karl Dönitz (; 16 September 1891 – 24 December 1980) was a German grand admiral and convicted war criminal who, following Adolf Hitler's Death of Adolf Hitler, suicide, succeeded him as head of state of Nazi Germany during the Second World ...
—approved a proposal to send two
Type IXD U-Boats
U-boats are naval submarines operated by Germany, including during the First and Second World Wars. The term is an anglicized form of the German word , a shortening of (), though the German term refers to any submarine. Austro-Hungarian Na ...
into Australian waters with the objective of tying down Allied anti-submarine assets in a secondary theatre. The U-boats involved were drawn from the ''
Monsun Gruppe
''Gruppe Monsun'' or Monsoon Group was a force of German U-boats (submarines) that operated in the Pacific and Indian Oceans during World War II. Although similar naming conventions were used for temporary groupings of submarines in the Atlanti ...
'' ("Monsoon Group"), and the two selected for this operation were and . An additional submarine——was added to this force at the end of September.
Due to the difficulty of maintaining German submarines in Japanese bases, the boats were not ready to depart from their bases in Penang and Batavia until early October. By this time, the Allies had intercepted and decoded German and Japanese messages describing the operation and were able to vector submarines onto the German boats. The
Dutch submarine ''Zwaardvisch'' sank ''U-168'' on 6 October near Surabaya and the American submarine sank ''U-537'' on 10 November near the northern end of the Lombok Strait. Due to the priority accorded to the Australian operation, was ordered to replace ''U-168''. ''U-196'' disappeared in the Sunda Strait some time after departing from Penang on 30 November. The cause of ''U-196''s loss is unknown, and was likely due to either an accident or a mechanical fault.
The only surviving submarine of the force assigned to attack Australia—''U-862'', under ''
Korvettenkapitän
(; ) is the lowest ranking Field officer, senior officer in the German navy.
Germany
Korvettenkapitän, short: KKpt/in lists: KK, () is the lowest senior officer military rank, rank () in the German Navy.
Address
The official manner, in li ...
''
Heinrich Timm—had left
Kiel
Kiel ( ; ) is the capital and most populous city in the northern Germany, German state of Schleswig-Holstein. With a population of around 250,000, it is Germany's largest city on the Baltic Sea. It is located on the Kieler Förde inlet of the Ba ...
in May 1944 and reached Penang on 9 September, sinking five merchantmen on the way. It departed Batavia on 18 November 1944, and arrived off the south west tip of Western Australia on 26 November. The submarine had great difficulty finding targets as the Australian naval authorities, warned of ''U-862''s approach, had directed shipping away from the routes normally used. ''U-862'' unsuccessfully attacked the Greek freighter ''Ilissos'' off the South Australian coast on 9 December, with bad weather spoiling both the attack and subsequent Australian efforts to locate the submarine.
Following her attack on ''Ilissos'', ''
U-862'' continued east along the Australian coastline, and entered the Pacific after passing to the south of
Tasmania
Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...
. The submarine achieved its first success on this patrol when it attacked the United States-registered
Liberty ship
Liberty ships were a ship class, class of cargo ship built in the United States during World War II under the Emergency Shipbuilding Program. Although British in concept, the design was adopted by the United States for its simple, low-cost cons ...
''Robert J. Walker'' off the southern coast of New South Wales on 24 December 1944. The ship sank the following day. ''U-862'' evaded an intensive search by Australian aircraft and warships and departed for New Zealand.
As ''U-862'' did not find any worthwhile targets off New Zealand, the submarine's commander planned to return to Australian waters in January 1945 and operate to the north of Sydney. ''U-862'' was ordered to break off her mission in mid-January, however, and return to Batavia. On its return voyage, the submarine sank another U.S. Liberty ship—''Peter Silvester''—approximately southwest of Fremantle on 6 February 1945. ''Peter Silvester'' was the last Allied ship to be sunk by the Axis in the Indian Ocean during the war. ''U-862'' arrived in Batavia in mid-February 1945 and is the only Axis ship known to have operated in Australian waters during 1945.
While Allied naval authorities were aware of the approach of the German strike force and were successful in sinking two of the four submarines dispatched, efforts to locate and sink ''U-862'' once she reached Australian waters were continually hampered by a lack of suitable ships and aircraft and a lack of personnel trained and experienced in anti-submarine warfare. As southern Australia was thousands of kilometres behind the active combat front in South-East Asia and had not been raided for several years, there were few anti-submarine assets available in this area in late 1944 and early 1945.
Conclusions
Casualties
Japanese submarines and ''U-862'' sank 30 ships in the area covered by the Australia Station during World War II. These ships had a combined
tonnage
Tonnage is a measure of the capacity of a ship, and is commonly used to assess fees on commercial shipping. The term derives from the taxation paid on '' tuns'' or casks of wine. In modern maritime usage, "tonnage" specifically refers to a cal ...
of . Nine other ships were damaged by Japanese submarines.
German surface raiders sank seven ships in Australian waters and captured another. Another merchant vessel was damaged by a mine.
The numbers of casualties resulting from German and Japanese attacks in Australian waters differ between sources. An unknown number of deaths and injuries were also caused by war-related accidents such as collisions between ships sailing together in convoys. The
official history
An official history is a work of history which is sponsored, authorised or endorsed by its subject. The term is most commonly used for histories which are produced for a government. The term also applies to commissions from non-state bodies includi ...
of Australia's role in World War II states that a total of 654 people were killed on board the vessels sunk by submarines, including approximately 200 Australian merchant seamen. It does not identify the number of people wounded in these attacks. The
Seamen's Union of Australia's post-war history put the number of Australian merchant seaman killed at 386, and research by the
Australian War Memorial
The Australian War Memorial (AWM) is a national war memorial, war museum, museum and archive dedicated to all Australians who died as a result of war, including peacekeeping duties. The AWM is located in Campbell, Australian Capital Territory, C ...
had by 1989 identified 520 Australian merchant seaman who had died.
Evidence on military casualties is fragmentary. Fatalities on RAN ships from enemy action in Australian waters include 645 men on ''Sydney'', 19 from ''Kuttabul'', 7 on board ships attacked at Darwin and 5 killed on ''Patricia Cam''. Several escort vessels also suffered fatalities that resulted from accidents. In his PhD
thesis
A thesis (: theses), or dissertation (abbreviated diss.), is a document submitted in support of candidature for an academic degree or professional qualification presenting the author's research and findings.International Standard ISO 7144: D ...
David Joseph Wilson estimated that at least 104 members of the RAAF were killed during maritime patrol and anti-submarine operations off the Australian coast, with at least 23 aircraft being destroyed.
Assessment
While the scale of the Axis naval offensive directed against Australia was small compared to other naval campaigns of the war such as the
Battle of the Atlantic
The Battle of the Atlantic, the longest continuous military campaign in World War II, ran from 1939 to the defeat of Nazi Germany in 1945, covering a major part of the naval history of World War II. At its core was the Allies of World War II, ...
, they were still "the most comprehensive and widespread series of offensive operations ever conducted by an enemy against Australia". Due to the limited size of the Australian shipping industry and the importance of sea transport to the Australian economy and Allied military in the South West Pacific, even modest shipping losses had the potential to seriously damage the Allied war effort in the
South West Pacific
Oceania ( , ) is a region, geographical region including Australasia, Melanesia, Micronesia, and Polynesia. Outside of the English-speaking world, Oceania is generally considered a continent, while Mainland Australia is regarded as its co ...
.
Despite the vulnerability of the Australian shipping industry, the Axis attacks did not seriously affect the Australian or Allied war effort. While the German surface raiders which operated against Australia caused considerable disruption to merchant shipping and tied down Allied naval vessels, they did not sink many ships and only operated in Australian waters for a few short periods. The effectiveness of the Japanese submarine campaign against Australia was limited by the inadequate numbers of submarines committed and flaws in Japan's submarine doctrine. The submarines were, however, successful in forcing the Allies to devote considerable resources to protecting shipping in Australian waters between 1942 and late 1943. The institution of coastal convoys between 1942 and 1943 may have also significantly reduced the efficiency of the Australian shipping industry during this period.
The performance of the Australian and Allied forces committed to the defence of shipping on the Australia station was mixed. While the threat to Australia from Axis raiders was "anticipated and addressed", only a small proportion of the Axis ships and submarines which attacked Australia were successfully located or engaged. Several German raiders operated undetected within Australian waters in 1940 as the number of Allied warships and aircraft available were not sufficient to patrol these waters and the loss of
HMAS ''Sydney'' was a high price to pay for sinking ''
Kormoran'' in 1941. While the Australian authorities were quick to implement convoys in 1942 and no convoyed ship was sunk during that year, the escorts of the convoys that were attacked in 1943 were not successful in either detecting any submarines before they launched their attack or successfully counter-attacking these submarines. Factors explaining the relatively poor performance of Australian anti-submarine forces include their typically low levels of experience and training, shortages of anti-submarine warfare assets, problems with co-ordinating searches and the poor
sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects o ...
conditions in the waters surrounding Australia. Nevertheless, "success in anti-submarine warfare cannot be measured simply by the total of sinkings achieved" and the Australian defenders may have successfully reduced the threat to shipping in Australian waters by making it harder for Japanese submarines to carry out attacks.
Remembrance
The naval operations in Australian waters during World War II were not publicised during the war, and have received relatively little attention from historians. This forms part of broader limitations in the literature on the defence of the Australian mainland during the war, which includes a lack of any published works providing a comprehensive single-volume history of the topic. The Australian official history series cover the campaigns from the viewpoint of each service separately, with the naval volumes providing an account of each of the sinkings in Australian waters throughout the war.
The official history does not cover the experiences of the
Merchant Navy, however. A large number of specialist Australian works discuss various aspects of the operations, and the history of the Seamen's Union of Australia covers the experiences of civilian mariners. Coverage of the Japanese submarine campaign against Australia in Japanese-language works is also limited.
There was little official recognition of the role played by the Merchant Navy in the years after the war. Merchant seaman were eventually issued with Merchant Navy War Service medals and were permitted to join
Anzac Day
Anzac Day is a national day of remembrance in Australia, New Zealand and Tonga that broadly commemorates all Australians and New Zealanders "who served and died in all wars, conflicts, and peacekeeping operations" and "the contribution and ...
marches from the mid-1970s. The surviving members of the Merchant Navy received the same access to military pensions as former service personnel in 1994. As of 2012, three major memorials had been erected to Australian merchant seamen who were killed in Australian waters during World War II. In 1950
BHP established a memorial to the seamen killed on board the ships it operated. This has since been moved to the banks of the Hunter River in central Newcastle. The national Merchant Seaman Memorial at the Australian War Memorial in
Canberra
Canberra ( ; ) is the capital city of Australia. Founded following the Federation of Australia, federation of the colonies of Australia as the seat of government for the new nation, it is Australia's list of cities in Australia, largest in ...
was dedicated in 1990. Another memorial is located at the
Australian National Maritime Museum
The Australian National Maritime Museum (ANMM) is a Australian government, federally operated maritime museum in Darling Harbour, Sydney. After considering the idea of establishing a maritime museum, the federal government announced that a nation ...
in Sydney. A number of small memorials to seamen killed in the war are located across Australia. Since 2008, Merchant Navy Day has been commemorated annually on 3 September and Battle for Australia Day has been observed on the first Wednesday of each September.
There are also several memorials to the military personnel killed in Australian waters. A memorial to HMAS ''Sydney'' was dedicated at Geraldton in November 2001. ''Kormoran''s crew erected a memorial to their ship while being held as prisoners of war at
Tatura
Tatura is a town in the Goulburn Valley region of Victoria, Australia, and is situated within the City of Greater Shepparton local government area, north of the state capital (Melbourne) and west of the regional centre of Shepparton, Victoria ...
. The loss of HMAS ''Kuttabul'' is commemorated by a memorial at the RAN's main base in Sydney (also named
HMAS ''Kuttabul'' in honour of the sunken ferry), and the RAN has hosted memorial services for the Japanese sailors killed in the raid on Sydney Harbour. A memorial for ''I-124'' is located in Darwin. The people killed in the campaign are buried or commemorated at
Commonwealth War Graves Commission
The Commonwealth War Graves Commission (CWGC) is an intergovernmental organisation of six independent member states whose principal function is to mark, record and maintain the graves and places of commemoration of Commonwealth of Nations mil ...
cemeteries and a large number of civil cemeteries in Australia. A memorial at
Rookwood Cemetery
Rookwood Cemetery (officially named Rookwood Necropolis) is a heritage-listed cemetery in Rookwood, Sydney, Australia. It is the largest necropolis in the Southern Hemisphere and is the world's largest remaining operating cemetery from the ...
in Sydney commemorates Australian service and Merchant Navy personnel killed Australian waters below the
20th parallel south
Following are circles of latitude between the 15th parallel south and the 20th parallel south:
16th parallel south
The 16th parallel south is a circle of latitude that is 16 degrees south of the Earth's equatorial plane. It crosses the Atlant ...
who have no known grave.
See also
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Axis naval activity in New Zealand waters
Notes
References
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*{{cite journal , last1=Stevens , first1=David , title=The War Cruise of the 1–6, March 1943 , journal=Australian Defence Force Journal , date=September–October 1993 , issue=102 , url=https://defence.gov.au/adc/adfj/Documents/issue_102/102_1993_Sep_Oct.pdf , issn=1320-2545
Conflicts in 1940
Conflicts in 1941
Conflicts in 1942
Conflicts in 1943
Conflicts in 1944
Conflicts in 1945
Military attacks against Australia
South West Pacific theatre of World War II
1940s in Australia
Military history of Japan during World War II
Australia–Japan relations