was a career naval officer in 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, when it was dissolved following Japan's surrender ...

, and a pioneer

submarine A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...

commander, known primarily as the commanding officer during the sinking of Submarine ''No.6''.

Biography

Born in Mikata District

Fukui prefecture is a prefecture of Japan located in the Chūbu region of Honshū. Fukui Prefecture has a population of 778,943 (1 June 2017) and has a geographic area of 4,190 km2 (1,617 sq mi). Fukui Prefecture borders Ishikawa Prefecture to the north, Gi ...

(present-day city of

Wakasa, Fukui is a Towns of Japan, town located in Fukui Prefecture, Japan. , the city had an estimated population of 14,577 and the population density of 82 persons per km². The total area of the town was . Geography Wakasa is located in southwestern Fuku ...

), to the family of a Shinto priest, Sakuma graduated from the 29th 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 stu ...

in 1901. One of his classmates was the future Navy Minister and

Prime Minister of Japan The prime minister of Japan (Japanese: 内閣総理大臣, Hepburn: ''Naikaku Sōri-Daijin'') is the head of government of Japan. The prime minister chairs the Cabinet of Japan and has the ability to select and dismiss its Ministers of Stat ...

Mitsumasa Yonai was a Japanese general and politician. He served as admiral in the Imperial Japanese Navy, Minister of the Navy, and Prime Minister of Japan in 1940. Early life and career Yonai was born on 2 March 1880, in Morioka, Iwate Prefecture, the firs ...

. He was assigned to the cruiser shortly before the start of the

Russo-Japanese War The Russo-Japanese War ( ja, 日露戦争, Nichiro sensō, Japanese-Russian War; russian: Ру́сско-япóнская войнá, Rússko-yapónskaya voyná) was fought between the Empire of Japan and the Russian Empire during 1904 and 1 ...

. He subsequently served with the 15th Torpedo Boat Flotilla, and was on board the cruiser during the

Battle of Tsushima The Battle of Tsushima (Japanese:対馬沖海戦, Tsushimaoki''-Kaisen'', russian: Цусимское сражение, ''Tsusimskoye srazheniye''), also known as the Battle of Tsushima Strait and the Naval Battle of Sea of Japan (Japanese: 日 ...

on May 26, 1905. After completing the

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, su ...

warfare school, Sakuma served on the

submarine tender A submarine tender is a type of depot ship that supplies and supports submarines. Development Submarines are small compared to most oceangoing vessels, and generally do not have the ability to carry large amounts of food, fuel, torpedoes, and ...

and was later a squad leader on the . He started to get involved in the submarine service in 1906, first taking the command of the ''No.4 submarine'', and eventually the Japan-built Holland-type ''No.6 '' in 1908. On April 15, 1910, while engaged in a practice dive in the

Inland Sea An inland sea (also known as an epeiric sea or an epicontinental sea) is a continental body of water which is very large and is either completely surrounded by dry land or connected to an ocean by a river, strait, or "arm of the sea". An inland se ...

off of the coast of

Yamaguchi Prefecture is a Prefectures of Japan, prefecture of Japan located in the Chūgoku region of Honshu. Yamaguchi Prefecture has a population of 1,377,631 (1 February 2018) and has a geographic area of 6,112 Square kilometre, km2 (2,359 Square mile, sq mi). Y ...

, the submarine suffered a malfunction resulting in the loss of the ship and crew. Two days later the submarine was recovered by Japanese authorities, and Sakuma's journal was found, with a detailed analysis of what may have caused the accident, ending with an apology to

Emperor Meiji , also called or , was the 122nd emperor of Japan according to the traditional order of succession. Reigning from 13 February 1867 to his death, he was the first monarch of the Empire of Japan and presided over the Meiji era. He was the figur ...

for the loss of the submarine and 14 crew members before the ship's air ran out. The journal was posted in later press reports, and Sakuma became a posthumous national hero and an example for courage and steadfastness within the Imperial Japanese Navy. CaptainTsutomuSakuma will

References

* Dupuy, Trevor N. ''

Harper Encyclopedia of Military Biography ''The Harper Encyclopedia of Military Biography'' () was written by Trevor N. Dupuy, Curt Johnson and David Bongard, and was issued in 1992 by HarperCollins Publishers. It contains more than three thousand short biographies of military figures fr ...

'', New York, 1992
Nishida, ''Imperial Japanese Navy''
written in Japanese) {{DEFAULTSORT:Sakuma, Tsutomu 1879 births 1910 deaths Imperial Japanese Navy officers Military personnel from Fukui Prefecture Japanese military personnel of the Russo-Japanese War