Joseph Stalin started his career as a student radical, becoming an influential member and eventually the leader of the Bolshevik faction of the Russian Social Democratic Labour Party. He served as the General Secretary of the Central Committee of the Communist Party of the Soviet Union from 1922 until his death in 1953. In December 1922 and early January 1923, Lenin is believed to have dictated a political will - though its authenticity is debated. It contains criticism of Stalin, and Leon Trotsky; Lenin primarily expressed a fear of a future fragmentation of the party.