The was a
fleet of the
Imperial Japanese Navy
The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, Potsdam Declaration, when it was dissolved followin ...
(IJN) established during
World War II
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 ...
.
History
The 8th Fleet was established on 14 July 1942 and was given the operational title of Outer South Seas Force, which reflected its mission of guarding conquests in the
South Pacific. In this respect, it essentially replaced the
4th Fleet, which was then given the operational title of Inner South Seas Force, and was primarily tasked with defending the
Mandates.
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 ...
Gunichi Mikawa
was a vice admiral in the Imperial Japanese Navy (IJN) during World War II. Mikawa was the commander of a heavy cruiser force that defeated the United States Navy (USN) and the Royal Australian Navy (RAN) at the Battle of Savo Island in Ironb ...
was appointed as the first
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 ...
of the 8th Fleet.

Initially, the 8th Fleet included the
''Takao''-class 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 ...
''Chōkai'' as its
flagship
A flagship is a vessel used by the commanding officer of a group of navy, naval ships, characteristically a flag officer entitled by custom to fly a distinguishing flag. Used more loosely, it is the lead ship in a fleet of vessels, typically ...
,
Cruiser Division 6 (CruDiv6) under
Rear Admiral
Rear admiral is a flag officer rank used by English-speaking navies. In most European navies, the equivalent rank is called counter admiral.
Rear admiral is usually immediately senior to commodore and immediately below vice admiral. It is ...
Aritomo Gotō with the entire
''Furutaka'' and
''Aoba'' classes of four older and somewhat smaller heavy cruisers (
''Aoba'',
''Kinugasa'',
''Kako'' and
''Furutaka''),
Cruiser Division 18 (CruDiv18) under Rear Admiral
Mitsuharu Matsuyama with three old
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 ...
s (
''Tenryū'',
''Tatsuta'' and
''Yūbari''), eight old
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 ...
s, and Submarine Squadron 7 (SubDiv7) with five
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. In addition, the minelayer
''Tsugaru'', the seaplane tender
''Kiyokawa Maru'', and the
2nd Air Group
was a unit of the Imperial Japanese Navy Air Service (IJNAS) during the Pacific War that was involved in the Guadalcanal Campaign, Solomon Islands Campaign and New Guinea Campaign. The air group was redesignated as the 582nd Air Group on 1 Novemb ...
were initially assigned to the 8th Fleet, where the latter was soon transferred to the
25th Air Flotilla of
11th Air Fleet
The was a grouping of naval aviation and surface units.
Assignments and Components
Commanders
Chiefs of Staff
Notes
References
*
{{Use dmy dates, date=June 2017
Fleets of the Imperial Japanese Navy
Units of the Imperial Japanese N ...
in August 1942.
On 25 July, Vice Admiral Mikawa led the fleet to
Truk in
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 ...
. From there he then moved to
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
New Britain
New Britain () is the largest island in the Bismarck Archipelago, part of the Islands Region of Papua New Guinea. It is separated from New Guinea by a northwest corner of the Solomon Sea (or with an island hop of Umboi Island, Umboi the Dampie ...
and arrived on 30 July, where he established his headquarters. He detached CruDiv6 under Rear Admiral Gotō to
Kavieng
Kavieng is the capital of the Papua New Guinean province of New Ireland and the largest town on the island of the same name. The town is located at Balgai Bay, on the northern tip of the island. As of 2009, it had a population of 17,248.
Kavi ...
on
New Ireland, in order to move them out of the range of
Allied aircraft. When the news of Allied landings on
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- ...
and
Tulagi
Tulagi, less commonly known as Tulaghi, is a small island in Solomon Islands, just off the south coast of Ngella Sule. The town of the same name on the island (pop. 1,750) was the capital of the British Solomon Islands Protectorate from 1896 t ...
reached the 8th Fleet headquarters on August 7, Mikawa promptly decided to make a night-time counter-attack with his available surface naval forces, despite the presence of American carriers. He ordered CruDiv6 to leave Kavieng to meet his flagship ''Chōkai''. Initially, Mikawa did not want to take the two available old light cruisers from CruDiv18 (''Tenryū'' and ''Yūbari''), since he deemed them as a liability due to their age and lack of crew training. Nevertheless, a stubborn staff officer of CruDiv18 managed to convince Mikawa to take them along. Only one destroyer (
''Yūnagi'') was available at the time to escort the striking force. After assembling the warships, Mikawa sailed toward Guadalcanal. Furthermore, He sent four submarines of SubDiv7 ahead of his surface striking force.
In the ensuing
Battle of Savo Island
The Battle of Savo Island, also known as the First Battle of Savo Island and in Japanese sources as the , and colloquially among Allied Guadalcanal veterans as the Battle of the Five Sitting Ducks, was a Naval warfare, naval battle during the So ...
in the early morning of 9 August, Admiral Mikawa's 8th Fleet defeated a numerically superior Allied Task Force 62.2, composed primarily 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 ...
vessels, but with a substantial
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 ...
component, all under the command of
British
British may refer to:
Peoples, culture, and language
* British people, nationals or natives of the United Kingdom, British Overseas Territories and Crown Dependencies.
* British national identity, the characteristics of British people and culture ...
Rear Admiral
Victor Crutchley. The striking force of the 8th Fleet sank four Allied heavy cruisers and additionally damaged one more heavy cruiser and two destroyers, in exchange for a relativity minor damage to two heavy cruisers and one destroyer. Nevertheless, they failed to follow through and destroy the lightly protected American transports that were in the process of landing critical supplies for the Allied troops on the ground. While CruDiv6 was returning to Kavieng on 10 August, heavy cruiser ''Kako'' was torpedoed and sunk by US submarine
S-44.
During the
Guadalcanal Campaign
The Guadalcanal campaign, also known as the Battle of Guadalcanal and codenamed Operation Watchtower by the United States, was an Allies of World War II, Allied offensive against forces of the Empire of Japan in the Solomon Islands during th ...
, the 8th Fleet was responsible for bringing reinforcements and supplies to the island. For this purpose Reinforcement Unit was formed, which was centered around Destroyer Squadron 2 led by Rear Admiral
Raizō Tanaka
was a rear admiral in the Imperial Japanese Navy (IJN) during most of World War II. A specialist in the heavy torpedoes that were carried by all the destroyers and cruisers of the IJN, Tanaka mainly commanded destroyer squadrons, with a cruis ...
. On 31 August, Tanaka was temporarily replaced in this role by Rear Admiral
Shintarō Hashimoto and his Destroyer Squadron 3. On 28 August 1942, the 8th Fleet also created the
R-Area Air Force, which exclusively operated
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 ...
in order to compensate for the lack of land 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 ...
area. The unit's primary mission was to protect
resupply convoys headed for Guadalcanal and to conduct
aerial reconnaissance
Aerial reconnaissance is reconnaissance for a military or Strategy, strategic purpose that is conducted using reconnaissance aircraft. The role of reconnaissance can fulfil a variety of requirements including Artillery observer, artillery spott ...
.

Since regular resupply runs by destroyers only could not deliver heavy equipment (such as
artillery
Artillery consists of ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and l ...
) to the
Imperial Japanese Army
The Imperial Japanese Army (IJA; , ''Dai-Nippon Teikoku Rikugun'', "Army of the Greater Japanese Empire") was the principal ground force of the Empire of Japan from 1871 to 1945. It played a central role in Japan’s rapid modernization during th ...
(IJA) on Guadalcanal, the 8th Fleet's Reinforcement Unit started using seaplane tenders
''Chitose'' and
''Nisshin'' as high-speed transports. To cover the unloading of supplies by the convoy on 11 October, the 8th Fleet assigned CruDiv6 with heavy cruisers ''Aoba'', ''Kinugasa'' and ''Furutaka'' and two destroyers under Rear Admiral Gotō to bombard the Allied position on Guadalcanal. On the night of 11/12 October they were ambushed by two heavy cruisers, two light cruisers and five destroyers under Rear Admiral
Norman Scott, which resulted in the
Battle of Cape Esperance
The Battle of Cape Esperance, also known as the Second Battle of Savo Island and in Japanese sources as the , took place on 11–12 October 1942, in the Pacific War, Pacific campaign of World War II between the Imperial Japanese Navy and United ...
. The battle accounted for the loss of ''Furutaka'' and one Japanese destroyer, in exchange for the loss of one US destroyer. Furthermore, Rear Admiral Gotō was also mortally wounded in the battle. Nevertheless, the convoy managed to successfully unload the supplies and equipment on Guadalcanal. Two of its destroyers, while retreating from Guadalcanal, were sunk by air attacks the following day. Another major resupply run was conducted on the night of 14/15 October by ''Nisshin'', while Vice Admiral Mikawa with ''Chōkai'' and ''Kinugasa'' shelled Allied position on Guadalcanal to cover the cargo unloading process.
The 8th Fleet was also involved in the
Naval Battle of Guadalcanal
The Naval Battle of Guadalcanal took place from 12 to 15 November 1942 and was the decisive engagement in a series of naval battles between Allies of World War II, Allied (primarily American) and Imperial Japanese Armed Forces, Imperial Japan ...
, where Vice Admiral Mikawa led a naval force that consisted of heavy cruisers ''Chōkai'', ''Kinugasa'',
''Maya'',
''Suzuya'', light cruisers
''Isuzu'' and ''Tenryū'', and four destroyers. In the early morning of November 14, ''Maya'' and ''Suzuya '' were detached under Rear Admiral
Shōji Nishimura
was an admiral in the Imperial Japanese Navy during World War II.
Biography
Nishimura was from Akita prefecture in the northern Tōhoku region of Japan. He was a graduate of the 39th class of the Imperial Japanese Naval Academy in 1911, ranki ...
to conduct a bombardment of the Allied position on Guadalcanal, before rendezvousing with Mikawa and the rest of the force after sunrise south of
New Georgia
New Georgia, with an area of , is the largest of the islands in Western Province (Solomon Islands), Western Province, Solomon Islands, and the List of islands by area, 203rd-largest island in the world. Since July 1978, the island has been par ...
. After that, they were repeatedly attacked by Allied aircraft throughout the morning, which sank ''Kinugasa'' and damaged ''Chōkai'', ''Maya'' and ''Isuzu''.

On 24 December 1942 the 8th Fleet came under the operational authority of the
Southeast Area Fleet. The 8th Fleet subsequently played a major role in
Operation KE
was the largely successful withdrawal of Japanese forces from Guadalcanal, concluding the Guadalcanal Campaign of . The operation took place between 14 January and 7 February 1943, and involved both Imperial Japanese Army (IJA) and Imperial ...
, the successful withdrawal of army forces from Guadalcanal during the first week of February 1943. Between 2–4 March eight destroyers from 8th Fleet under Rear Admiral
Masatomi Kimura escorted a major reinforcement convoy from Rabaul to
Lae on
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 ...
. In the ensuing
Battle of the Bismarck Sea
The Battle of the Bismarck Sea (2–4 March 1943) took place in the South West Pacific Area (SWPA) during World War II when aircraft of the U.S. Fifth Air Force and the Royal Australian Air Force (RAAF) attacked a Japanese convoy carrying tro ...
the Japanese suffered a major defeat when Allied aircraft sank four destroyers and all eight transports. Shortly after this debacle, Vice Admiral Mikawa was relieved of the 8th Fleet command and replaced by Vice Admiral
Tomoshige Samejima
Vice Admiral Baron , was an admiral in the Imperial Japanese Navy during World War II.
Biography
Samejima was the grandson of Iwakura Tomomi, and adopted by Admiral Samejima Kazunori a native of Satsuma Domain and noted figure in the Meiji re ...
.
Later in the war, the 8th Fleet headquarters staff was isolated on
Bougainville Island
Bougainville Island (; Tok Pisin: ''Bogenvil'') is the main island of the Autonomous Region of Bougainville, which is part of Papua New Guinea. Its land area is . The highest point is Mount Balbi, on the main island, at .
The much smaller Buk ...
with remnants of
Imperial Japanese Army
The Imperial Japanese Army (IJA; , ''Dai-Nippon Teikoku Rikugun'', "Army of the Greater Japanese Empire") was the principal ground force of the Empire of Japan from 1871 to 1945. It played a central role in Japan’s rapid modernization during th ...
forces.
Commanders of the 8th Fleet
Commander in chief
[Wendel, Axis History Database]
Chief of staff
References
Notes
Books
*
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*
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*
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*
External links
*
*
*
{{Imperial Japanese Navy warship units
8
Naval units and formations of Imperial Japan
Military units and formations established in 1942
Military units and formations disestablished in 1945
1945 disestablishments in Japan