was a career officer in the Imperial Japanese Navy

Imperial Japanese Navy

The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...

 during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

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Biography

In Kōchi prefecture

Kochi Prefecture

is a prefecture of Japan located on the south coast of Shikoku. The capital is the city of Kōchi.- History :Prior to the Meiji Restoration, Kōchi was known as Tosa Province and was controlled by the Chosokabe clan in the Sengoku period and the Yamauchi family during the Edo period.- Geography...

, Oishi graduated from the 48th class of the Imperial Japanese Naval Academy

Imperial Japanese Naval Academy

The was a school established to train officers for the Imperial Japanese Navy. It originally located in Nagasaki, moved to Yokohama in 1866, and was relocated to Tsukiji, Tokyo in 1869. It moved to Etajima, Hiroshima in 1888...

 in 1920, with a ranking of 13th out of a class of 171 cadets. As a midshipman

Midshipman

A midshipman is an officer cadet, or a commissioned officer of the lowest rank, in the Royal Navy, United States Navy, and many Commonwealth navies. Commonwealth countries which use the rank include Australia, New Zealand, South Africa, India, Pakistan, Singapore, Sri Lanka and Kenya...

, he served on the cruiser

Cruiser

A cruiser is a type of warship. The term has been in use for several hundreds of years, and has had different meanings throughout this period...

  and battleship

Battleship

A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...

 . After his promotion to ensign

Ensign (rank)

Ensign is a junior rank of a commissioned officer in the armed forces of some countries, normally in the infantry or navy. As the junior officer in an infantry regiment was traditionally the carrier of the ensign flag, the rank itself acquired the name....

 in 1921, he was assigned to the destroyer

Destroyer

In naval terminology, a destroyer is a fast and maneuverable yet long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller, powerful, short-range attackers. Destroyers, originally called torpedo-boat destroyers in 1892, evolved from...

 , followed by the oiler Shiretoko, and then the battleship .

After his promotion to lieutenant

Lieutenant

A lieutenant is a junior commissioned officer in many nations' armed forces. Typically, the rank of lieutenant in naval usage, while still a junior officer rank, is senior to the army rank...

 on 1 December 1925, he specialized in navigation and served as chief navigator on the destroyers and , submarine tender

Submarine tender

A submarine tender is a type of ship that supplies and supports submarines.Submarines are small compared to most oceangoing vessels, and generally do not have the ability to carry large amounts of food, fuel, torpedoes, and other supplies, nor to carry a full array of maintenance equipment and...

 Jingei

Jingei class submarine tender

The was a class of submarine tenders of the Imperial Japanese Navy , and served from the 1920s through World War II. Two vessels of this class were built between 1922 and 1924 under the Eight-eight fleet plan.-Background:...

, and cruiser .

Oishi graduated from the Naval Staff College

Naval War College (Japan)

The was the staff college of the Imperial Japanese Navy, responsible for training officers for command positions either on warships, or in staff roles....

 in 1930 and was promoted to lieutenant commander

Lieutenant Commander

Lieutenant Commander is a commissioned officer rank in many navies. The rank is superior to a lieutenant and subordinate to a commander...

 in 1932. He served as chief torpedo

Torpedo

The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

 officer on the cruiser . After his promotion to commander

Commander

Commander is a naval rank which is also sometimes used as a military title depending on the individual customs of a given military service. Commander is also used as a rank or title in some organizations outside of the armed forces, particularly in police and law enforcement.-Commander as a naval...

 in 1937, he received his first command: the gunboat

Gunboat

A gunboat is a naval watercraft designed for the express purpose of carrying one or more guns to bombard coastal targets, as opposed to those military craft designed for naval warfare, or for ferrying troops or supplies.-History:...

  in 1938. He subsequently served in number of staff positions, including assignments to the 1st Carrier Strike Force of the Combined Fleet

Combined Fleet

The was the main ocean-going component of the Imperial Japanese Navy. The Combined Fleet was not a standing force, but a temporary force formed for the duration of a conflict or major naval maneuvers from various units normally under separate commands in peacetime....

 and 1st Air Fleet

1st Air Fleet of the Imperial Japanese Navy

The Imperial Japanese Navy at the beginning of World War II contained the world's largest carrier fleet. At the centre, was the 1st Air Fleet which was a grouping of naval aircraft and aircraft carriers...

, participating the all major carrier operations from the attack on Pearl Harbor

Attack on Pearl Harbor

The attack on Pearl Harbor was a surprise military strike conducted by the Imperial Japanese Navy against the United States naval base at Pearl Harbor, Hawaii, on the morning of December 7, 1941...

 to the Battle of Midway

Battle of Midway

The Battle of Midway is widely regarded as the most important naval battle of the Pacific Campaign of World War II. Between 4 and 7 June 1942, approximately one month after the Battle of the Coral Sea and six months after Japan's attack on Pearl Harbor, the United States Navy decisively defeated...

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On 25 August 1942, Oishi was assigned command of Aikoku Maru, a merchant raider

Merchant raider

Merchant raiders are ships which disguise themselves as non-combatant merchant vessels, whilst actually being armed and intending to attack enemy commerce. Germany used several merchant raiders early in World War I, and again early in World War II...

, and was promoted to captain the same year. In September, Aikoku Maru was assigned to the Southwest Area Fleet (IJN 8th Fleet

IJN 8th Fleet

The was a fleet of the Imperial Japanese Navy established during World War II.-History:Established on 14 July 1942, the IJN 8th Fleet was a headquarters unit established to direct Japanese naval operations in the Solomon Islands and New Guinea...

) and tasked to transport elements of General Tanayoshi Sano's IJA 38th Division to Rabaul

Rabaul

Rabaul is a township in East New Britain province, Papua New Guinea. The town was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash of a volcanic eruption. During the eruption, ash was sent thousands of metres into the air and the...

 for the reinforcement of Guadalcanal

Guadalcanal

Guadalcanal is a tropical island in the South-Western Pacific. The largest island in the Solomons, it was discovered by the Spanish expedition of Alvaro de Mendaña in 1568...

. In November 1942, while on a raiding mission in the Indian Ocean

Japanese raiders in Indian Ocean Campaign

Japanese raiders in the Indian Ocean Campaign were converted merchant ships which would often use their comprehensive armament to cause havoc in the Indian Ocean.-Background:...

, Aikoku Maru sank the Royal Dutch Shell

Royal Dutch Shell

Royal Dutch Shell plc , commonly known as Shell, is a global oil and gas company headquartered in The Hague, Netherlands and with its registered office in London, United Kingdom. It is the fifth-largest company in the world according to a composite measure by Forbes magazine and one of the six...

 tanker Ondina. In December 1943-April 1944, Aikoku Maru participated in reinforcement operations to New Guinea

New Guinea

New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...

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On 3 April 1943, Oishi was recalled to Japan, and held several shore positions until the end of the war. He died on 13 February 1946, and was promoted on rear-admiral posthumously.