樺太庁
He was born Tōichi Kurihara (栗原 登一) in Toyohara, Karafuto Prefecture. In October 1945, he joined the Democratic Youth League of Japan. In 1947, he joined the Japanese Communist Party. In 1953, he left the Japanese Communist Party. In 1955, he and Kanichi Kuroda established the Japan Revolutionary Communist League, thus becoming leader of the Fourth International in Japan. In 1957, he established the Japanese Trotskyist League (日本トロツキスト連盟 "Nihon Trotskyist Renmei").