The reforms consisted of changing or removing key institutions that helped Stalin hold power: the cult of personality that surrounded him, the Stalinist political system, and the Gulag labour-camp system, all of which had been created and dominated by him. Stalin was succeeded by a collective leadership after his death in March 1953, consisting of Georgi Malenkov, Premier of the Soviet Union; Lavrentiy Beria, head of the Ministry of the Interior; and Nikita Khrushchev, First Secretary of the Central Committee of the Communist Party of the Soviet Union (CPSU).