Nikita Khrushchev became Premier of the Soviet Union after Joseph Stalin's death in 1953. He denounced Stalin's crimes in a 1956 speech, starting de-Stalinization. As Premier, Khrushchev oversaw reforms and improved relations with the West, but also clashes like the Cuban Missile Crisis. He was ousted in 1964 due to agricultural failures and alienating other leaders with his reforms and international incidents.