Vladimir Lenin was a Russian revolutionary, politician, and political theorist. He was the first Premier of the Soviet Union after its declaration following the First Russian Civil War. His ideology of Leninism was the main ruling force over the country for most of its existence.
Lenin first embraced socialist politics at an early age following his brother's execution for protesting the Tsarist regime. He then spent the next couple decades engaging in his own opposition, eventually becoming a founding member of the Russian Social Democratic Labour Party. When the party fractured, Lenin led the 'Bolshevik' faction, which advocated for an active revolutionary overthrow of the monarchy.
During the First World War, Lenin returned to Russia and took the lead during the October Revolution, which sought to overthrow the Russian Provisional Government that had already unseated Tsar Nicholas. Following the First Russian Civil War, which lasted from 1917 to 1923, the Soviet Union was established and Lenin became its first Premier. He only held power for a year, as in 1924 he would die following a series of strokes, with his close associate, Leon Trotsky, succeeding him to the position.