Answer:
The Soviet Union had previously supported Castro's attempts to promote communism in Cuba and the Americas.
Step-by-step explanation:
The Cuban Missile Crisis took place in October 1962, when the United States and the Soviet Union mutually threatened to use nuclear weapons if necessary. The crisis was the most dangerous event of the Cold War, and probably the closest world has ever been to a nuclear war between the two nuclear powers.
The crisis occurred after the United States had deployed nuclear-armed missiles in Turkey and Italy, and in response to this, the Soviet Union began to set up a series of rocket launchers for mid-range rockets. Fully operational, these rockets would reach Washington D.C. and a number of other strategic goals in the United States. The crisis occurred from October 16, 1962, when Soviet missile installations in Cuba were identified, and 13 days until October 28, 1962, when Soviet leader Nikita Khrushchev announced that the installations in Cuba would be dismantled.