On September 28, 1965, six years after he led the Cuban Revolution and four years after the failed U.S.-backed Bay of Pigs Invasion, Fidel Castro announces that any Cuban who wished to leave the island was free to do so. With Cuban forces no longer blocking civilians from leaving, a massive wave of emigration ensued, bringing hundreds of thousands of Cuban immigrants to Florida.
Political repression had brought about Castro's revolution, but much remained the same under the new regime. As Castro became increasingly vocal about his belief in socialism and opposition to American imperialism, he faced dissent from political opponents at home and hostility from the American political establishment. The year after the Bay of Pigs, the United States and Soviet Union nearly went to war over the latter's placement of nuclear missiles on the island. Due to the recent hostilities, many Americans assumed Castro was behind the assassination of President John F. Kennedy in 1963, although no such evidence has ever emerged. Castro refused to allow Cubans to leave for America, although a number of dissenters and supporters of the deposed Batista regime did succeed in escaping.
With further anti-government protests and widespread poverty, due in part to the American embargo on all trade with Cuba, Castro believed his society was close to the breaking point. He therefore announced on September 28th that those who wished to leave were free to do so. Immediately, several thousand refugees boarded boats at the port of Camarioca, leading to a haphazard crossing that threatened to overwhelm the U.S. Coast Guard and immigration authorities. As the continuation of such perilous crossings was in neither's interest, the U.S. and Cuba engaged in surprisingly cooperative negotiations, resulting in the "Freedom Flights" airlift program.
For the next eight years, ten flights a week left Cuba for Miami, and many Cubans waited years for their spot on the planes. Roughly 300,000 made the trip. This mass movement of people had several major effects on both countries. Castro was able to rid the island of many dissenters, although their departure was a propaganda victory for the Americans and may have led to significant "brain drain" in Cuba. It also markedly changed the demographics of Miami—it was during this period that the city's Little Havana neighborhood became a permanent enclave for Cuban culture.