Vladimir Ilyich Ulyanov, better known by the alias Lenin, was a Russian communist revolutionary, politician and political theorist. He served as head of government of Soviet Russia from 1917 to 1924 and of the Soviet Union from 1922 to 1924. Under his administration, Russia and then the wider Soviet Union became a one-party communist state governed by the Russian Communist Party. Ideologically a Marxist, he developed political theories known as Leninism.
Born to a wealthy middle-class family in Simbirsk, Lenin embraced revolutionary socialist politics following his brother's 1887 execution. Expelled from Kazan Imperial University for participating in protests against the Russian Empire's Tsarist government, he devoted the following years to a law degree. He moved to Saint Petersburg in 1893 and became a senior Marxist activist. In 1897, he was arrested for sedition and exiled to Shushenskoye for three years, where he married Nadezhda Krupskaya. After his exile, he moved to Western Europe, where he became a prominent theorist in the Marxist Russian Social Democratic Labour Party.