Born Sept. 20, 1880, in Wakasano, district of Ako, Hyogo Prefecture; died Nov. 30, 1955, in Tokyo. Japanese public figure.
Oyama graduated in 1905 from Waseda University in Tokyo, where he attended the School of Political Science and Economics. In 1906 he became an instructor at Waseda University, and in 1915 a professor. Joining the staff of the newspaper Osaka Asahi Shimbun in 1917, he attacked in print the Japanese imperialist interference that took place in the Soviet Far East between 1918 and 1922. He was chairman of the Workers’ and Peasants’ Party from 1926 to 1928 and of the new Workers’ and Peasants’ Party from 1929 to 1931.
In 1932, Oyama emigrated to the USA, where he engaged in research at Northwestern University in Evanston, Ill. He returned to Japan in 1947.
Oyama played an important role in convoking the First National Congress for the Defense of Peace, held in Japan in April 1949. In 1950 he became chairman of the Japanese Committee for the Defense of Peace, and in 1951 a member of the Bureau of the World Peace Council. He helped organize the First International Conference for the Prohibition of Atomic and Hydrogen Weapons, held in Hiroshima in August 1955. From 1930 to 1932 and from 1950 to 1955 he was a deputy to the Japanese parliament. In 1951, Oyama was awarded the International Lenin Prize for Strengthening Peace Between Nations.