By 1960, Fidel Castro had taken over Cuba. He quickly started removing the United States from his country. He seized private property and accused the government of undermining him. Many business owners with interests in Cuba protested this treatment. The encouraged the U.S. government to do something about it.
They decided to invade. The CIA trained a large group of 1200 people for this task. Then in April of 1961, they invaded using the Bay of Pigs. They failed with most of the men captured and made prisoners. Fidel Castro decided to use these men to negotiate for supplies for his country. He first demanded 500 tractors.
This started a quiet tractors for freedom movement as the government tried to raise enough money. Impatient, Castro changed his demand to money. Eventually, they settled on money and some other supplies. With this, the prisoners went home after spending 20 months as prisoners.