Vladimir Lenin (22 April, 1870 - 21 January 1924). Russian revolutionary, politician, and political theorist. He served as the first and founding head of government of Soviet Russia from 1917 to 1924 and of the Soviet Union from 1922 to 1924. Under his administration, Russia, and later the Soviet Union, became a one-party socialist state governed by the Soviet Communist Party. A Marxist, he developed a variant of this communist ideology known as Leninism.