Harvard Law School
Years of service
1900 - 1947
Empire of Japan
June 15, 1880 Kochi, Kochi Prefecture, Japan (
Marshal Admiral Fleet Admiral General Staff
World War I World War II
Grand Cordon of the Order of the Sacred Treasure (1st class) Order of the Golden Kite (3rd class) Order of the Rising Sun (3rd class)
January 5, 1947, Tokyo, Japan
Japanese cruiser Hirado
Shigetaro Shimada, Yoshijiro Umezu, Hajime Sugiyama, Koshiro Oikawa, Hideki Tojo
Imperial Japanese Navy
Admiral of the Fleet Osami Nagano (永野 修身, Nagano Osami, June 15, 1880 – January 5, 1947) was a Japanese career naval officer and Admiral of the Fleet in the Imperial Japanese Navy from 1943. He was more of an administrative officer than a sea commander. From April 1941 to February 1944, he was Chief of the Imperial Japanese Navy General Staff. He was the founder of the Chiba Institute of Technology.
Nagano was born in Kōchi to an ex-samurai family. In 1900, he graduated from the 28th class of the Imperial Japanese Naval Academy, ranked second in his class of 105 cadets. After midshipman service on the cruiser Hashidate and battleship Asahi, he was commissioned an ensign and assigned to the cruiser Asama. During the Russo-Japanese War, he served in a number of staff positions. The closest he came to combat was as commander of a land-based heavy naval gun unit during the siege of Port Arthur.
After his promotion to lieutenant in 1905, Nagano served on the battleship Shikishima. From 1905 to 1906, he studied naval artillery and navigation. From 1906 to 1908, he was chief gunnery officer on the cruiser Itsukushima. In 1909, he graduated from the Japanese Naval War College.
In 1910, Nagano was promoted to lieutenant commander and assigned as chief gunnery officer on the battleship Katori. From January 1913 to April 1915, he was a language officer in the United States, during which time he studied at Harvard Law School.
During World War I, Nagano was executive officer on the cruisers Nisshin and cruiser Iwate. In 1918, he was promoted to captain. In 1919, he received his first (and only) ship command, the cruiser Hirado.
From December 1920, Nagano was a military attaché to the United States, in which capacity he attended the Washington Naval Conference. In November 1923, he returned home, although he returned to the United States on official visits in 1927 and 1933. In December 1923, he was promoted to rear admiral.
In February 1924, Nagano was chief of the Imperial Japanese Navy General Staff Third Section (Intelligence). From December 1924, he commanded the 3rd Battleship Division. From April 1925, he commanded the 1st China Expeditionary Fleet. In December 1927, he was promoted to vice admiral. From 1928 to 1929, Nagano was commandant of the Imperial Japanese Naval Academy. From 1930 to 1931, he was vice chief of the Navy General Staff, in which capacity he attended the Geneva Naval Conference. In 1930, he attended the London Naval Conference. From 1933 to 1934, he was commander in chief of the Yokosuka Naval District. On 1 March 1934, he was promoted to admiral and appointed to the Supreme War Council. Nagano was the chief naval delegate to the London Naval Conference of 1935. Japan withdrew in protest from the 1935 London Conference after it was denied naval parity with the United States and Great Britain.
In 1936, Nagano was appointed Navy Minister under Prime Minister Kōki Hirota. In 1937, he was appointed Combined Fleet commander-in-chief.
From 1941, Nagano was chief of the Imperial Japanese Naval General Staff, serving as the most senior officer in the Japanese navy during most of World War II. However, he did not provide strong leadership and entrusted too much strategic planning to hard-line subordinates. Although he was a proponent of the Nanshin-ron, he was against war with the United States. He concluded that if Japan were able to take over British and Dutch colonies in Asia without directly attacking the United States, the isolationist factions with the American government would prevent the United States from declaring war against Japan. He was against Admiral Isoroku Yamamoto's planned attack on Pearl Harbor, but reluctantly gave his approval for the attack after Yamamoto threatened to resign as Combined Fleet commander.
In 1943, Nagano was promoted to marshal admiral. By 1944, however, Japan had suffered serious military setbacks and Nagano had lost the confidence of Emperor Hirohito. With the emperor's approval, Prime Minister Hideki Tōjō and Navy Minister Shigetarō Shimada removed Nagano from his post and replaced him with Shimada. Nagano spent the remainder of the war as an advisor to the government.
War crimes trial
After World War II in 1945, the American Occupation forces arrested Nagano. He was charged with Class A war criminal charges before the International Military Tribunal for the Far East in Tokyo. When US naval officers interrogated him, he was described as "thoroughly cooperative", "keenly alert", "intelligent", and "anxious to develop American friendship". He died of a heart attack due to complications arising from pneumonia in Sugamo Prison in Tokyo before the conclusion of his trial.