When the Soviets arrived to crush the Prague Spring, 1968

About 250,000 Soviet and Warsaw Pact troops invaded Czechoslovakia from August 20 to 21, 1968, to prevent a blossoming political and cultural liberalization, the sudden end of the Prague Spring and the strengthening of the Kremlin's hold.

The first months of 1968 brought a renaissance of political and cultural life in the then Czechoslovakia. Journalists and students were calling for an end to censorship, public rallies in support of reform began in Prague and beyond, and that year's May Day commemoration was seized upon by those demanding more freedom.

Upon assuming the Czechoslovak leadership in January becoming the First Secretary of the Communist Party of Czechoslovakia, Alexander Dubek announced his intention to proceed with liberalization that included freedom of speech and religion, an end to censorship and travel restrictions, and industrial and agricultural reforms. Improvement

By April the government had published an "action program" outlining Dubsek's plans to establish "socialism with a human face".

The plan provided for a gradual democratization of the political system, economic liberalization over a period of 10 years, and called for communists to compete with other parties in future elections. The government officially ended its censorship policy in June.

Alarmed by these moves and as the beginning of the end of Czechoslovak communism, several fellow Warsaw Pact nations expressed their objections in a July communiqué, stating that the Czechoslovak reform program "endangers the common vital interests of other socialist countries".

Soviet leader Leonid Brezhnev tried to slow the pace of the Prague Spring with a series of talks, meeting directly with Dubek in late July in the small border town of Serna nad Tissou.

Brezhnev called for the removal of prominent reformers from leadership positions and tightening restrictions on the media; Dubek defended the reformist moves, while reiterating his commitment to the Warsaw Pact and the Eastern Bloc Economic Coalition, known as COMCON. Unhappy, by mid-August the Kremlin had decided to intervene more forcefully.

Shortly before midnight on 20 August, 250,000 Soviet and Warsaw Pact troops from Poland, Hungary, Bulgaria and East Germany (Romania and Albania refused to participate) invaded Czechoslovakia to end reform efforts, In which the occupying army was ultimately 500,000. "Operation Danube" was the largest military mobilization in Europe since the end of World War II.

Although Soviet action on Czechoslovakia was swift and successful, small-scale resistance continued in early 1969 while the Soviets struggled to establish a stable government. Finally, in April of 1969, the Soviet Union forced Dubsek to be removed from power in favor of a more conservative administrator.

In subsequent years, the new leadership re-established government censorship and control to prevent freedom of movement, but it also improved economic conditions, eliminating one of the sources of revolutionary enthusiasm. Czechoslovakia once again became a cooperative member of the Warsaw Pact.

After the invasion, the Soviet leadership justified the use of force in Prague, which would become known as the Brezhnev Doctrine, which stated that Moscow had the right to intervene in any country where a communist government was threatened. .

This doctrine, established to justify Soviet action in Czechoslovakia, also became the primary justification for the Soviet invasion of Afghanistan in 1979, and even before that it helped to finalize the Sino-Soviet split, as Beijing feared the Soviet Union. would use the doctrine as a justification for attacking or interfering with Chinese communism.