Kingoro Hashimoto was born in 1890 in Okayama, Japan. He became an officer in the Japanese Army, graduating from the Military Academy in 1911.
He was Military Attaché to the Japanese embassy in Turkey, then Chief of the Japanese Special Service in Manchuria. He became a Colonel in 1933.
Kingoro Hashimoto is said to have been a firm proponent of the military dictatorship and to have pushed for Japanese expansion by the forceful annexation of Manchuria.
He was alleged to have participated in the March and October plots in 1931, aimed at overthrowing the government through a coup d’état. He is also reported to have been involved in a 1932 plot to assassinate Prime Minister Inukai.
In addition Kingoro Hashimoto is alleged to have been a member of various clubs whose aim was to get rid of democracy and which supported the establishment of a form of government more disposed to going to war.
It was also alleged that Kingoro Hashimoto had played a role in the Moukden incident of 18 September 1931, which provided the pretext a few months later for the annexation of Manchuria by Japan.
In 1944, Kingoro Hashimoto was elected to the Chamber of Representatives. A few months later, he became Vice-President of the Diet, the Japanese Parliament.
At the end of the war, Kingoro Hashimoto was arrested and brought before the International Military Tribunal for the Far East.