In 1959 Fidel Castro and his forces (who famously included Che Guevara and Camilo Cienfuegos) overthrew the Batista regime in Cuba. Castro went on to establish a one party state in collaboration with the communists. In 1960 the new government began the nationalisation of land and private property in Cuba, including US companies. The US responded with a trade embargo, and Castro turned to the Soviet Union for support.
In 1961 CIA-trained Cuban dissidents landed at the Bay of Pigs in an attempt to overthrow Castro. The attempt failed, serving only to strengthen the Cuban/Soviet alliance. During 1962, an American U-2 spy plane revealed that the Soviet Union had installed nuclear weapons and ballistic missiles in Cuba.
On 22 October 1962 the United States, with NATO support, blockaded Soviet ships entering the waters around Cuba. As Soviet ships approached the blockade line, tensions between the superpowers intensified and the world seemed on the brink of nuclear war. At the last moment, the Soviet ships turned back.
On 28 October Nikita Khrushchev agreed to stop shipments and to remove, under UN supervision, the weapons already in Cuba. In return the US agreed not to make another attempt to overthrow Castro's government. The Cuban Crisis marked the end of a fraught period in the Cold War, leading to a more cooperative period in US-Soviet relations, termed 'détente'.