Baron was a general in the

Imperial Japanese Army The was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor o ...

and Army Minister during

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

. His son,

Hiroshi Ōshima Baron was a general in the Imperial Japanese Army, Japanese ambassador to Germany before and during World War II and (unwittingly) a major source of communications intelligence for the Allies. His role was perhaps best summed up by General Geo ...

was a

lieutenant general Lieutenant general (Lt Gen, LTG and similar) is a three-star military rank (NATO code OF-8) used in many countries. The rank traces its origins to the Middle Ages, where the title of lieutenant general was held by the second-in-command on the ...

in the Imperial Japanese Army, and served as Japanese ambassador to

Nazi Germany Nazi Germany (lit. "National Socialist State"), ' (lit. "Nazi State") for short; also ' (lit. "National Socialist Germany") (officially known as the German Reich from 1933 until 1943, and the Greater German Reich from 1943 to 1945) was ...

Biography

Ōshima was born in Iwamura Domain,

Mino Province was a province of Japan in the area of Japan that is today southern Gifu Prefecture. Mino was bordered by Ōmi to the west, Echizen and Hida to the north, and Shinano to the east, and Ise, Mikawa, and Owari to the south. Its abbreviat ...

(currently part of

Ena City 300px, Ena City Hall is a city located in Gifu, Japan. , the city had an estimated population of 48,777, and a population density of 96.7 persons per km², in 19,820 households. The total area of the city was . Geography Ena is located in the T ...

Gifu Prefecture is a prefecture of Japan located in the Chūbu region of Honshu. Gifu Prefecture has a population of 1,991,390 () and has a geographic area of . Gifu Prefecture borders Toyama Prefecture to the north; Ishikawa Prefecture to the northwest, F ...

) as the son of a

samurai were the hereditary military nobility and officer caste of medieval and early-modern Japan from the late 12th century until their abolition in 1876. They were the well-paid retainers of the '' daimyo'' (the great feudal landholders). They h ...

household. He graduated from the 4th class of the

Imperial Japanese Army Academy The was the principal officer's training school for the Imperial Japanese Army. The programme consisted of a junior course for graduates of local army cadet schools and for those who had completed four years of middle school, and a senior course f ...

in 1881, where he specialized in

artillery Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during siege ...

and was sent overseas as a

military attaché A military attaché is a military expert who is attached to a diplomatic mission, often an embassy. This type of attaché post is normally filled by a high-ranking military officer, who retains a commission while serving with an embassy. Opport ...

and for studies to

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

and

Prussia Prussia, , Old Prussian: ''Prūsa'' or ''Prūsija'' was a German state on the southeast coast of the Baltic Sea. It formed the German Empire under Prussian rule when it united the German states in 1871. It was ''de facto'' dissolved by an em ...

from 1891 to 1893. Ōshima served on the staff of General

Yamagata Aritomo ''Gensui (Imperial Japanese Army), Gensui'' Prince , also known as Prince Yamagata Kyōsuke, was a senior-ranking Japanese people, Japanese military commander, twice-elected Prime Minister of Japan, and a leading member of the ''genrō'', an � ...

during the

Japanese First Army The was an army of the Imperial Japanese Army. It was raised and demobilized on three occasions. History The Japanese 1st Army was initially raised during the First Sino-Japanese War from 1 September 1894 – 28 May 1895 under the command of ...

First Sino-Japanese War The First Sino-Japanese War (25 July 1894 – 17 April 1895) was a conflict between China and Japan primarily over influence in Korea. After more than six months of unbroken successes by Japanese land and naval forces and the loss of the po ...

. During 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 served on the

Imperial General Headquarters The was part of the Supreme War Council and was established in 1893 to coordinate efforts between the Imperial Japanese Army and Imperial Japanese Navy during wartime. In terms of function, it was approximately equivalent to the United States ...

, and after the war held various administrative and staff positions within the

Imperial Japanese Army General Staff The , also called the Army General Staff, was one of the two principal agencies charged with overseeing the Imperial Japanese Army. Role The was created in April 1872, along with the Navy Ministry, to replace the Ministry of Military Affairs ...

. He was promoted to

major general Major general (abbreviated MG, maj. gen. and similar) is a military rank used in many countries. It is derived from the older rank of sergeant major general. The disappearance of the "sergeant" in the title explains the apparent confusion of a ...

in 1907 and to

in 1913. From 30 April 1916 to 29 September 1918, Ōshima was

Minister of War A defence minister or minister of defence is a cabinet official position in charge of a ministry of defense, which regulates the armed forces in sovereign states. The role of a defence minister varies considerably from country to country; in som ...

under

Prime Ministers A prime minister, premier or chief of cabinet is the head of the cabinet and the leader of the ministers in the executive branch of government, often in a parliamentary or semi-presidential system. Under those systems, a prime minister is not ...

Ōkuma Shigenobu Marquess was a Japanese statesman and a prominent member of the Meiji oligarchy. He served as Prime Minister of the Empire of Japan in 1898 and from 1914 to 1916. Ōkuma was also an early advocate of Western science and culture in Japan, and ...

and

Terauchi Masatake Gensui Count Terauchi Masatake ( ja, 寺内正毅), GCB (5 February 1852 – 3 November 1919), was a Japanese military officer, proconsul and politician. He was a '' Gensui'' (or Marshal) in the Imperial Japanese Army and the Prime Minister o ...

. He entered the reserves in 1919 and served as a member of the House of Peers in the

Diet of Japan The is the national legislature of Japan. It is composed of a lower house, called the House of Representatives (, ''Shūgiin''), and an upper house, the House of Councillors (, '' Sangiin''). Both houses are directly elected under a paralle ...

from 1920. From 1940-1946, he was a member of the

Privy Council A privy council is a body that advises the head of state of a state, typically, but not always, in the context of a monarchic government. The word "privy" means "private" or "secret"; thus, a privy council was originally a committee of the mon ...

Ken'ichi Ōshima with Giichi Tanaka and Yūsaku Uehara

Decorations

* 1895 –

Order of the Sacred Treasure The is a Japanese order, established on 4 January 1888 by Emperor Meiji as the Order of Meiji. Originally awarded in eight classes (from 8th to 1st, in ascending order of importance), since 2003 it has been awarded in six classes, the lowest ...

, 6th class * 1895 – JPN Kyokujitsu-sho 4Class BAR

Order of the Rising Sun The is a Japanese order, established in 1875 by Emperor Meiji. The Order was the first national decoration awarded by the Japanese government, created on 10 April 1875 by decree of the Council of State. The badge features rays of sunlight ...

, 4th class * 1895 – JPN Kinshi-kunsho 5Class BAR

Order of the Golden Kite The was an order of the Empire of Japan, established on 12 February 1890 by Emperor Meiji "in commemoration of Jimmu Tennō, the Romulus of Japan". It was officially abolished 1947 by the Supreme Commander for the Allied Powers (SCAP) during th ...

, 5th class * 1900 – JPN Zuiho-sho (WW2) 5Class BAR