Born 1889; died Nov. 14, 1939. Figure in the revolutionary movement; Soviet state figure. Member of the Communist Party from 1906. Born in Moscow.
Mantsev studied in the department of law at Moscow University. He participated in the Revolution of 1905-07. He was repeatedly arrested for revolutionary activities, and in 1911 he fled from exile. He was an emigre from 1911 to 1913. In 1913 he returned illegally to Russia but was arrested and exiled to Vologda Province. In 1916 he was drafted into the army. In the fall of 1917 he was elected to the Moscow regional bureau of Soviets and participated in the preparation of the October Armed Uprising in Moscow. In September 1918 he began working in the All-Russian Extraordinary Commission for the Struggle Against Counterrevolution and Sabotage as head of the investigations department and as vice-chairman of the Moscow Cheka. In late 1919 he became director of the Special Section of the Southern and Southwestern fronts. In July 1920 he became a member of the collegium of the All-Russian Cheka. In 1921-23 he was in the state security agencies in the Ukraine, and was chairman of the Ukrainian Cheka (later, State Political Directorate), and in March 1922 he became people’s commissar of internal affairs of the Ukrainian SSR.
At the Twelfth Party Congress, Mantsev was elected a member of the Central Control Commission of the RCP (Bolshevik). In August 1923 he became a member of the collegium of the People’s Commissariat of the Workers’ and Peasants’ Inspectorate and a member of the collegium of the Unified State Political Directorate. From 1924 to 1936 he was director of the Planning and Economic Administration of the Supreme Council on the National Economy, deputy people’s commissar of finances of the USSR, and a member of the Central Executive Committee of the USSR at the seventh convocation. He was a delegate to the Thirteenth, Fifteenth, and Sixteenth Party Congresses. In 1936 and 1937 he was chairman of the Special Collegium and vice-chairman of the Supreme Court of the RSFSR. He was awarded the Order of the Red Banner and the Order of the Red Banner of Labor.