was a Japanese
Marshal Admiral and
commander-in-chief 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 ...
's
Combined Fleet
The was the main sea-going component of the Imperial Japanese Navy. Until 1933, the Combined Fleet was not a permanent organization, but a temporary force formed for the duration of a conflict or major naval maneuvers from various units norm ...
.
Biography
Early life and career
Koga was born in the ceramics center of
Arita in
Nishimatsuura County of
Saga Prefecture
is a Prefectures of Japan, prefecture of Japan located on the island of Kyushu. Saga Prefecture has a population of roughly 780,000 and has a geographic area of . Saga Prefecture borders Fukuoka Prefecture to the northeast and Nagasaki Prefect ...
in 1885. He entered the 34th class of the
Imperial Japanese Naval Academy
The was a school established to train line officers for the Imperial Japanese Navy. It was originally located in Nagasaki, moved to Yokohama in 1866, and was relocated to Tsukiji, Tokyo, in 1869. It moved to Etajima, Hiroshima, in 1888. Students ...
and graduated in 1906, ranked 14th of 176 cadets.
He served as
midshipman
A midshipman is an officer of the lowest Military rank#Subordinate/student officer, rank in the Royal Navy, United States Navy, and many Commonwealth of Nations, Commonwealth navies. Commonwealth countries which use the rank include Royal Cana ...
on the
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 ...
on its long-distance navigational training cruise to
Honolulu
Honolulu ( ; ) is the List of capitals in the United States, capital and most populous city of the U.S. state of Hawaii, located in the Pacific Ocean. It is the county seat of the Consolidated city-county, consolidated City and County of Honol ...
,
Hilo
Hilo () is the largest settlement in and the county seat of Hawaii County, Hawaiʻi, United States, which encompasses the Island of Hawaiʻi, and is a census-designated place (CDP). The population was 44,186 according to the 2020 census. I ...
,
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 ...
,
Brisbane
Brisbane ( ; ) is the List of Australian capital cities, capital and largest city of the States and territories of Australia, state of Queensland and the list of cities in Australia by population, third-most populous city in Australia, with a ...
,
Palm Island, Queensland
Palm Island is a Suburbs and localities (Australia), locality consisting of an island group of 16 islands, split between the Shire of Hinchinbrook and the Aboriginal Shire of Palm Island, in Queensland, Australia. The locality coincides with th ...
,
Batavia,
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 ...
,
Mako
, better known by the mononym name Mako (sometimes stylised MAKO), is a Japanese Voice acting in Japan, voice actress, singing, singer and a member of the band Bon-Bon Blanco, in which her prominent role is as the maraca player. She has also perf ...
,
Qingdao
Qingdao, Mandarin: , (Qingdao Mandarin: t͡ɕʰiŋ˧˩ tɒ˥) is a prefecture-level city in the eastern Shandong Province of China. Located on China's Yellow Sea coast, Qingdao was long an important fortress. In 1897, the city was ceded to G ...
,
Port Arthur,
Dairen
Dalian ( ) is a major sub-provincial port city in Liaoning province, People's Republic of China, and is Liaoning's second largest city (after the provincial capital Shenyang) and the third-most populous city of Northeast China (after Shenyang ...
,
Chemulpo
Incheon is a city located in northwestern South Korea, bordering Seoul and Gyeonggi Province to the east. Inhabited since the Neolithic, Incheon was home to just 4,700 people when it became an international port in 1883. As of February 2020, ...
,
Chinkai,
Busan
Busan (), officially Busan Metropolitan City, is South Korea's second list of cities in South Korea by population, most populous city after Seoul, with a population of over 3.3 million as of 2024. Formerly romanized as Pusan, it is the economi ...
and
Kagoshima
, is the capital Cities of Japan, city of Kagoshima Prefecture, Japan. , the city had an estimated population of 583,966 in 285,992 households, and a population density of 1100 persons per km2. The total area of the city is .
Etymology
While the ...
. On his return, he was commissioned as
ensign
Ensign most often refers to:
* Ensign (flag), a flag flown on a vessel to indicate nationality
* Ensign (rank), a navy (and former army) officer rank
Ensign or The Ensign may also refer to:
Places
* Ensign, Alberta, Alberta, Canada
* Ensign, Ka ...
and assigned to the , followed by and .
As a
sub-lieutenant he served on the and , and as
lieutenant
A lieutenant ( , ; abbreviated Lt., Lt, LT, Lieut and similar) is a Junior officer, junior commissioned officer rank in the armed forces of many nations, as well as fire services, emergency medical services, Security agency, security services ...
from 1911, he served on .
After further attendance at
Japan's Naval War College, Koga held shore staff posting following his graduation and promotion to
lieutenant commander in 1917. In 1920, having seen no action during
World War I
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...
, Koga became a resident officer in France. He returned in 1922 to become
executive officer
An executive officer is a person who is principally responsible for leading all or part of an organization, although the exact nature of the role varies depending on the organization.
In many militaries and police forces, an executive officer ...
on the . On his promotion to
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 ...
on December 1, 1926, Koga was again posted to France, where he served as a
naval attaché
A navy, naval force, military maritime fleet, war navy, or maritime force is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake-borne, riverine, littoral, or ocean-borne combat operations ...
in Paris until November 1, 1928.
Recalled to Japan in 1930 and being given command of the
Yokosuka Naval Station, Koga captained the
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 ...
from December 31, 1930, and the
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 ...
from December 31, 1931, until his appointment to
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 ...
on December 31, 1932 and transfer to be Chief of the
Imperial Japanese Navy General Staff
The was the highest organ within the Imperial Japanese Navy (IJN). In charge of planning and operations, it was headed by an Admiral headquartered in Tokyo.
History
Created in 1893, the Navy General Staff took over operational (as opposed to a ...
's Intelligence Division in 1933.
Koga became Vice Chief of the
Navy General Staff and was promoted to
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 ...
on December 31, 1936 shortly before the beginning of the
Second Sino-Japanese War
The Second Sino-Japanese War was fought between the Republic of China (1912–1949), Republic of China and the Empire of Japan between 1937 and 1945, following a period of war localized to Manchuria that started in 1931. It is considered part ...
in 1937.
Commander of the
IJN 2nd Fleet
The was a fleet of the Imperial Japanese Navy (IJN) created as a mobile strike force in response to hostilities with Russia, and saw action in every IJN military operation until the end of World War II.
History
Established on 27 October 1903, ...
in 1939, Koga was placed in command of the
China Area Fleet
The was a fleet of the Imperial Japanese Navy organized after the Battle of Shanghai. It reported directly to the Imperial General Headquarters and had the same organizational level as the Combined Fleet. This article handles their predecessor f ...
on September 1, 1941. Koga shared Yamamoto's misgivings about war with the United States, but disagreed with Yamamoto regarding the use of
naval aviation
Naval aviation / Aeronaval is the application of Military aviation, military air power by Navy, navies, whether from warships that embark aircraft, or land bases.
It often involves ''navalised aircraft'', specifically designed for naval use.
Seab ...
, remaining a firm battleship advocate until events later in the
Pacific War
The Pacific War, sometimes called the Asia–Pacific War or the Pacific Theatre, was the Theater (warfare), theatre of World War II fought between the Empire of Japan and the Allies of World War II, Allies in East Asia, East and Southeast As ...
proved his position outdated.
Pacific War
Battle of Hong Kong
With the start of the
Pacific War
The Pacific War, sometimes called the Asia–Pacific War or the Pacific Theatre, was the Theater (warfare), theatre of World War II fought between the Empire of Japan and the Allies of World War II, Allies in East Asia, East and Southeast As ...
, Koga commanded naval operations during the
Battle of Hong Kong
The Battle of Hong Kong (8–25 December 1941), also known as the Defence of Hong Kong and the Fall of Hong Kong, was one of the first battles of the Pacific War in World War II. On the same morning as the attack on Pearl Harbor, forces of the ...
from December 9, 1941 to the end of the month.
Commander in Chief of the Combined Fleet
Following the death of Admiral
Isoroku Yamamoto
was a Marshal Admiral of the Imperial Japanese Navy (IJN) and the commander-in-chief of the Combined Fleet during World War II. He commanded the fleet from 1939 until his death in 1943, overseeing the start of the Pacific War in 1941 and J ...
on April 18, 1943, Koga succeeded Yamamoto as
Commander in Chief of the Combined Fleet. His
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 ...
was the battleship . Koga attempted to revitalize Japanese naval operations by reorganization of the
Combined Fleet
The was the main sea-going component of the Imperial Japanese Navy. Until 1933, the Combined Fleet was not a permanent organization, but a temporary force formed for the duration of a conflict or major naval maneuvers from various units norm ...
into task forces built around
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 in imitation of the
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 ...
, and organized a land-based naval air fleet to work in coordination with the carriers. Operationally, he intended to mount an aggressive counteroffensive, first in the
Aleutians
The Aleutian Islands ( ; ; , "land of the Aleuts"; possibly from the Chukchi ''aliat'', or "island")—also called the Aleut Islands, Aleutic Islands, or, before 1867, the Catherine Archipelago—are a chain of 14 main, larger volcanic island ...
to dilute American forces and eventually to lure the American fleet into a major naval engagement in late 1943. However, the losses of Japan's land and carrier based aircraft in the Southwest Pacific eventually forced a Japanese withdrawal from the
Solomons to the aero-naval base complex at
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 ...
in the
Bismarcks by the end of the year, and the simultaneous defeat in the
Gilbert Islands
The Gilbert Islands (;Reilly Ridgell. ''Pacific Nations and Territories: The Islands of Micronesia, Melanesia, and Polynesia.'' 3rd. Ed. Honolulu: Bess Press, 1995. p. 95. formerly Kingsmill or King's-Mill IslandsVery often, this name applied o ...
of the Central Pacific in November 1943. Koga gradually adopted a more conservative stance, attempting to conserve his remaining forces for a decisive battle to inflict maximum damage on the Americans when they closed toward the 'Inner Defense Lines' of the
Marianas
The Mariana Islands ( ; ), also simply the Marianas, are a crescent-shaped archipelago comprising the summits of fifteen longitudinally oriented, mostly Volcano#Dormant and reactivated, dormant volcanic mountains in the northwestern Pacific Ocean ...
and Philippines (code named "
Z plan"). An additional strategic change in late 1943 was the establishment of the Grand Escort Command of better organized convoys and increased ASW vessels in the face of increasingly successful U.S. submarine attacks on Empire shipping lanes, although this would not be nearly enough to prevent the collapse of the Japanese merchant marine over the following year.
Death
Koga was killed when his plane, a
Kawanishi H8K
The Kawanishi H8K is a flying boat used by the Imperial Japanese Navy Air Service during World War II for Maritime patrol aircraft, maritime patrol duties. The World War II Allied names for Japanese aircraft, Allied reporting name for the type wa ...
("Emily")
flying boat
A flying boat is a type of seaplane with a hull, allowing it to land on water. It differs from a floatplane in having a fuselage that is purpose-designed for flotation, while floatplanes rely on fuselage-mounted floats for buoyancy.
Though ...
, crashed during a
typhoon
A typhoon is a tropical cyclone that develops between 180° and 100°E in the Northern Hemisphere and which produces sustained hurricane-force winds of at least . This region is referred to as the Northwestern Pacific Basin, accounting for a ...
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
Davao while he was overseeing the withdrawal of the Combined Fleet from its Palau headquarters on March 31, 1944. His Chief of staff, Vice Admiral
Shigeru Fukudome
was an admiral and Chief of Staff of the Imperial Japanese Navy during World War II.
Biography
Early life and career
Born in Yonago, Tottori prefecture, Fukudome graduated from the 40th class of the Imperial Japanese Naval Academy in 1912, ra ...
, survived ditching in a second airplane off
Cebu
Cebu ( ; ), officially the Province of Cebu (; ), is a province of the Philippines located in the Central Visayas region, and consists of a main island and 167 surrounding islands and islets. The coastal zone of Cebu is identified as a ...
and was held captive by Filipino guerrillas, during which time
Koga's battle plans found their way into Allied hands.
[Bradsher, The Z-PLan Story] His death was not announced until May 1944 when he was formally replaced by Admiral
Soemu Toyoda
was an admiral in the Imperial Japanese Navy in World War II.
Biography Early career
Toyoda was born in what is now part Kitsuki city, Ōita Prefecture. He graduated from the 33rd class of the Imperial Japanese Navy Academy in 1905, ranked ...
. From page 20 of ''I Was A Kamikaze'', by Ryuji Nagatsuka: After describing reversals at Rabaul and
Truk, he adds "The death of Admiral Koga, successor to Admiral Yamamoto, had been another shock for the Japanese nation. These distressing circumstances had forced the naval and military Chiefs of Staff to resign. They had been replaced by
General Tojo and
Admiral Shimada." From then on, Prime Minister Tojo held both the portfolio of the Minister of Armed Forces and the post of Chief of Imperial General Staff in the army.
Koga was promoted to
Marshal Admiral posthumously and he was accorded a
state funeral
A state funeral is a public funeral ceremony, observing the strict rules of protocol, held to honour people of national significance. State funerals usually include much pomp and ceremony as well as religious overtones and distinctive elements o ...
. His grave is at the
Tama Cemetery
in Tokyo is the largest municipal cemetery in Japan. It is split between the cities of Fuchū, Tokyo, Fuchu and Koganei, Tokyo, Koganei within the Tokyo Metropolis. First established in April 1923 as , it was redesignated Tama Cemetery in 1935. ...
, outside of Tokyo.
References
Books
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External links
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Notes
{{DEFAULTSORT:Koga, Mineichi
1885 births
1944 deaths
Military personnel from Saga Prefecture
Imperial Japanese Navy marshal admirals
Imperial Japanese Navy personnel killed in World War II
Japanese admirals of World War II
Recipients of the Knight's Cross of the Iron Cross with Oak Leaves
Recipients of the Order of the Rising Sun
Recipients of the Order of the Sacred Treasure
Recipients of the Order of the Golden Kite
Japanese naval attachés