Sentaro Omori
Encyclopedia
, was an admiral in the Imperial Japanese Navy
during World War II
.
and graduated from the 41st class of the Imperial Japanese Naval Academy
in 1913. He was ranked 16th out of 118 cadets. He served his midshipman
duty aboard the cruiser
, battleship
s and , and was commissioned as an ensign
in 1914. He subsequently served on the battleship and destroyer
.
Ōmori returned to school, and became a torpedo
expert. He served as lieutenant
on the destroyers and and the battleship before being given his first command on 1 December 1923: the destroyer .
Through the 1920 and 1930s, Ōmori subsequently commanded the destroyers , and , seaplane tender
Kawakami Maru, and finally the battleship from 1939–1940, while steadily increasing in rank and returning at regular intervals to torpedo school to remain expert on the latest developments in torpedo technology and tactics. He was promoted to rear admiral
on 15 November 1940.
, Ōmori was in command of Destroyer Squadron 1 (DesRon1), which accompanied the main strike force during the attack on Pearl Harbor
. It also participated in the Indian Ocean Raid
of early 1942. During the Battle of Midway
, DesRon1 directed the occupation of Attu Island
in the Battle of the Aleutian Islands
. Omori was subsequently promoted to vice admiral
, and given command of Cruiser Division 5 (CruDiv5). Assigned to the Solomon Islands
, he was ordered to attack American transports off Bougainville Island
in early November 1943. In the resultant Battle of Empress Augusta Bay
of 1–2 November 1943, the Japanese forces (heavy cruiser
s and , light cruiser
s and , and destroyers , , , , , and ) suffered a decisive defeat. Ōmori and his heavy cruisers narrowly escaped damage in an air raid at Rabaul
, New Britain
the following day, and retreated to the main Japanese base at Truk, Caroline Islands
. Ōmori was relieved of his command for having withdrawn at Empress Augusta Bay against an inferior force and was sent back to Japan.
Ōmori became Commandant of the Torpedo School, and was promoted to vice admiral
on 1 July 1944. He was director of the Special Attack Division from 13 September 1944–10 August 1945, supervising work with the Kaiten
human-guided torpedoes. At the very end of World War II
, he was appointed Commander in Chief of the IJN 7th Fleet
.
Ōmori died on 24 December 1974.
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...
.
Early life
Ōmori was born in Kumamoto prefectureKumamoto Prefecture
is a prefecture of Japan located on Kyushu Island. The capital is the city of Kumamoto.- History :Historically the area was called Higo Province; and the province was renamed Kumamoto during the Meiji Restoration. The creation of prefectures was part of the abolition of the feudal system...
and graduated from the 41st 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 1913. He was ranked 16th out of 118 cadets. He served his 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...
duty aboard 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...
, 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...
s and , and was commissioned as an 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 1914. He subsequently served on the battleship and 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...
.
Ōmori returned to school, and became a 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...
expert. He served as 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 the destroyers and and the battleship before being given his first command on 1 December 1923: the destroyer .
Through the 1920 and 1930s, Ōmori subsequently commanded the destroyers , and , seaplane tender
Seaplane tender
A seaplane tender is a ship that provides facilities for operating seaplanes. These ships were the first aircraft carriers and appeared just before the First World War.-History:...
Kawakami Maru, and finally the battleship from 1939–1940, while steadily increasing in rank and returning at regular intervals to torpedo school to remain expert on the latest developments in torpedo technology and tactics. He was promoted to rear admiral
Rear Admiral
Rear admiral is a naval commissioned officer rank above that of a commodore and captain, and below that of a vice admiral. It is generally regarded as the lowest of the "admiral" ranks, which are also sometimes referred to as "flag officers" or "flag ranks"...
on 15 November 1940.
World War II
At the start of World War IIWorld 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...
, Ōmori was in command of Destroyer Squadron 1 (DesRon1), which accompanied the main strike force during 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...
. It also participated in the Indian Ocean Raid
Indian Ocean raid
The Indian Ocean raid was a naval sortie by the Fast Carrier Strike Force of the Imperial Japanese Navy from 31 March-10 April 1942 against Allied shipping and bases in the Indian Ocean. It was an early engagement of the Pacific campaign of World War II...
of early 1942. During 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...
, DesRon1 directed the occupation of Attu Island
Attu Island
Attu is the westernmost and largest island in the Near Islands group of the Aleutian Islands of Alaska, making it the westernmost point of land relative to Alaska and the United States. It was the site of the only World War II land battle fought on the incorporated territory of the United States ,...
in the Battle of the Aleutian Islands
Battle of the Aleutian Islands
The Aleutian Islands Campaign was a struggle over the Aleutian Islands, part of Alaska, in the Pacific campaign of World War II starting on 3 June 1942. A small Japanese force occupied the islands of Attu and Kiska, but the remoteness of the islands and the difficulties of weather and terrain meant...
. Omori was subsequently promoted to vice admiral
Vice Admiral
Vice admiral is a senior naval rank of a three-star flag officer, which is equivalent to lieutenant general in the other uniformed services. A vice admiral is typically senior to a rear admiral and junior to an admiral...
, and given command of Cruiser Division 5 (CruDiv5). Assigned to the Solomon Islands
Solomon Islands
Solomon Islands is a sovereign state in Oceania, east of Papua New Guinea, consisting of nearly one thousand islands. It covers a land mass of . The capital, Honiara, is located on the island of Guadalcanal...
, he was ordered to attack American transports off Bougainville Island
Bougainville Island
Bougainville Island is the main island of the Autonomous Region of Bougainville of Papua New Guinea. This region is also known as Bougainville Province or the North Solomons. The population of the province is 175,160 , which includes the adjacent island of Buka and assorted outlying islands...
in early November 1943. In the resultant Battle of Empress Augusta Bay
Battle of Empress Augusta Bay
The Battle of Empress Augusta Bay, on 1–2 November 1943—also known as the Battle of Gazelle Bay, Operation Cherry Blossom, and in Japanese sources as the Sea Battle of Bougainville Bay Shore —was a naval battle fought near the island of Bougainville...
of 1–2 November 1943, the Japanese forces (heavy cruiser
Heavy cruiser
The heavy cruiser was a type of cruiser, a naval warship designed for long range, high speed and an armament of naval guns roughly 203mm calibre . The heavy cruiser can be seen as a lineage of ship design from 1915 until 1945, although the term 'heavy cruiser' only came into formal use in 1930...
s and , light cruiser
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...
s and , and destroyers , , , , , and ) suffered a decisive defeat. Ōmori and his heavy cruisers narrowly escaped damage in an air raid at 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...
, New Britain
New Britain
New Britain, or Niu Briten, is the largest island in the Bismarck Archipelago of Papua New Guinea. It is separated from the island of New Guinea by the Dampier and Vitiaz Straits and from New Ireland by St. George's Channel...
the following day, and retreated to the main Japanese base at Truk, Caroline Islands
Caroline Islands
The Caroline Islands 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 in the eastern part of the group, and Palau at the extreme western end...
. Ōmori was relieved of his command for having withdrawn at Empress Augusta Bay against an inferior force and was sent back to Japan.
Ōmori became Commandant of the Torpedo School, and was promoted to vice admiral
Vice Admiral
Vice admiral is a senior naval rank of a three-star flag officer, which is equivalent to lieutenant general in the other uniformed services. A vice admiral is typically senior to a rear admiral and junior to an admiral...
on 1 July 1944. He was director of the Special Attack Division from 13 September 1944–10 August 1945, supervising work with the Kaiten
Kaiten
The Kaiten were manned torpedos and suicide craft, they were used by the Imperial Japanese Navy in the final stages of World War II.-History:...
human-guided torpedoes. At the very end of 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...
, he was appointed Commander in Chief of the IJN 7th Fleet
IJN 7th Fleet
The was a fleet of the Imperial Japanese Navy during World War II, primarily responsible for control of the Tsushima Strait.-History:The IJN 7th Fleet was formed on 15 April 1945, during the closing stages of World War II...
.
Ōmori died on 24 December 1974.