In the years following its independence, the Cuban republic saw significant economic development, but also political corruption and a succession of despotic leaders, culminating in the overthrow of the dictator Fulgencio Batista by the 26th of July Movement, led by Fidel Castro, during the 1953–1959 Cuban Revolution. The new government aligned with the Soviet Union and embraced communism. In the early 1960s, Castro's regime withstood invasion (April 1961), faced nuclear Armageddon (October 1962), and experienced a civil war (October 1960) that included Dominican support for regime opponents. Following the Warsaw Pact invasion of Czechoslovakia (1968), Castro publicly declared Cuba's support. His speech marked the start of Cuba's complete absorption into the Eastern Bloc. By the mid-1970s, little would remain of Cuba's political or economic system. During the Cold War, Cuba also supported Soviet policy in Afghanistan, Poland, Angola, Ethiopia, Nicaragua, and El Salvador. The Soviet-Cuban intervention in Angola contributed to the downfall of the apartheid regime in South Africa.