Joseph Vissarionovich Stalin was the ruler of the Soviet Union from 1927 until 1953. He served as both General Secretary of the Communist Party of the Soviet Union (1922–1952) and Chairman of the Council of Ministers of the Soviet Union (1941–1953). Initially governing the country as part of a collective leadership, he consolidated power to become the Soviet Union's de facto dictator by the 1930s. A communist ideologically committed to the Leninist interpretation of Marxism, Stalin formalised these ideas as Marxism–Leninism while his own policies are known as Stalinism.