1968: Crushing of the Prague Spring

A statue of the Catholic king St Wenceslas, on Wenceslas Square, Prague, in February 1968. Czechoslovakia is at the beginning of a period of political liberalisation after the reformist Alexander Dubček comes to power as prime minister Photograph: James P. Blair/Getty

Dubček smiles as he speaks to Communist party leaders on May 1. With popular support, he has begun rolling back communist orthodoxy in the economy and moving towards democracy by granting more freedom to the media and individuals Photograph: Bettmann/Corbis

Students during a sit-in. As liberalisation rolls forward and anti-Soviet opinions begin appearing in the press, the USSR and leaders of the Warsaw pact countries become concerned about Dubček's reforms, fearing they could spread to their own countries Photograph: Getty

Prague youngsters holding a flag stand atop an overturned truck as other residents surround Soviet tanks Photograph: AFP

A Czech girl shouts "Ivan go home!" at soldiers sitting on a tank in Prague Photograph: Corbis

Prague residents holding Czechoslovakian flags demonstrate in Wenceslas Square Photograph: AFP

An anti-Russia demonstration Photograph: Rex Features

Prague residents carrying a Czechoslovakian flag and throwing burning torches attempt to stop a Soviet tank Photograph: AFP

Demonstrators throw stones at Russian tanks Photograph: Rex Features

A man tries to help people killed and wounded in Prague Photograph: AFP

A car passes dozens of Russian tanks Photograph: Bill Ray/Getty

Czechoslovakian refugees at the Austrian borders, end of August Photograph: Getty

Austrian refugee camp for Czechoslovakians Photograph: Getty

August 31: A man stands amidst the wreckage left by the Soviet invasion Photograph: AFP

September 3: Students distribute underground literature in Wenceslas Square Photograph: Corbis

September 10: Czechoslovakians listen to a radio for news of the uprising Photograph: Corbis

January 24 1969: People pay tribute in Wenceslas Square where Jan Palach burned himself to death earlier that month to protest against the Soviet occupation. At left is a picture of Palach; in the middle is Alexander Dubček; and on the right is the Czechoslovakian president, Ludvík Svoboda Photograph: Gerard Leroux/AFP

Tens of thousands of people follow Jan Palach's coffin. His name becomes synonymous with the ill-fated Prague Spring Photograph: Henri Bureau/Corbis