Warsaw Pact invasion of Czechoslovakia

Late on the night of 20 August 1968, armies of the Soviet Union, Poland, Bulgaria and Hungary crossed into Czechoslovakia to put an end to the reforms of the Prague Spring. Code-named Operation Danube, the invasion involved some 250,000 troops on its first night and met little armed resistance, though 137 Czechoslovaks were killed. It crushed the hope of a reformed, more open communism in the Soviet bloc for two decades.

Czechoslovakia's economy had stagnated in the early 1960s, and pressure for change grew inside the Communist Party. On 5 January 1968 the reformer Alexander Dubček replaced Antonín Novotný as party leader. His Action Programme of April promised freer speech, press and travel, more room for the market, a federation of Czechs and Slovaks and limits on the secret police, all under continued party leadership. Censorship was lifted, and the press began to examine the crimes of the Stalinist years. Dubček called the project "socialism with a human face".

The Soviet leader Leonid Brezhnev and the heads of neighbouring communist states feared that Czechoslovakia might drift out of the Warsaw Pact and that reform would spread to their own countries. The East German and Polish leaders, Walter Ulbricht and Władysław Gomułka, pressed hardest for intervention. Talks at Čierna nad Tisou in July and a declaration signed in Bratislava on 3 August seemed to settle matters, as Dubček pledged loyalty to the alliance. But hardliners within the Czechoslovak leadership were secretly preparing to unseat him and asked Moscow for help, and on 18 August Brezhnev told allied leaders that the invasion would go ahead.

Around midnight on 20–21 August, some 250,000 soldiers crossed the border with some 2,000 tanks; the force later grew to roughly half a million. Soviet troops outnumbered the others five to one. Romania refused to take part, Albania left the Warsaw Pact soon afterwards, and East German units were held back at the last moment for fear of recalling the German occupation three decades earlier. Soviet special forces seized Prague's airport for an airlift, and armoured columns reached the capital almost unopposed. The Czechoslovak army, lacking an independent chain of command, offered no effective resistance, and Dubček urged the population not to fight. The hardliners' plan to vote Dubček out collapsed when news of the invasion reached the party Presidium, which condemned it by seven votes to four.

Dubček and other reformers were arrested and flown to Moscow. Across the country, people met the soldiers with arguments, refused them food and water, painted slogans and took down street signs. President Ludvík Svoboda refused to appoint a puppet government and went to Moscow himself. After days of pressure, the Czechoslovak delegation, with the single exception of František Kriegel, signed the Moscow Protocol, which restored censorship and ordered the removal of reformers. Dubček returned to Prague on 27 August, still nominally in charge.

On 16 January 1969 the student Jan Palach set himself on fire in Prague's Wenceslas Square in protest; he died three days later. In April 1969 Dubček was replaced by Gustáv Husák, who reversed the reforms, purged the party and drove critics out of their jobs. Many of them later formed the dissident movement that led the Velvet Revolution in 1989. Some 70,000 people fled immediately after the invasion, and around 300,000 emigrated before 1989. The doctrine that Moscow could intervene to protect socialism in an allied state became known as the Brezhnev Doctrine.

Western governments condemned the invasion but did not intervene; the United States was absorbed in the Vietnam War and keen on arms talks with Moscow. Eight protesters who unfurled banners in Red Square were arrested. In Bucharest, Nicolae Ceaușescu denounced the invasion, a stand that won him popularity at home (see Romanian revolution of 1989). On 4 December 1989 the Soviet Union and its allies formally declared the invasion a mistake.

Our 1960 and 1985 maps show Czechoslovakia within the Soviet bloc; the 1994 map shows its successor states, the Czech Republic and Slovakia.