Today, in 2008, the Czech Republic and the Slovak Republic are two independent, democratic states and members of the EU and NATO. Forty years ago, more precisely on 21 August 1968, this thought would have failed to provoke even a smirk in Prague and Bratislava - so far-fetched, so very remote was any chance for change and self-determination. On that summer day, troops of the Warsaw Pact invaded Czechoslovakia with 460 000 soldiers and 7000 tanks. It was the largest military operation since the Second World War. With this act of force, the Soviet Union brought a brief period of social and political freedom to a grinding halt. This abrupt end to a period of feverish reform activity went down in history as the Prague Spring. August 2008 marks the 40th anniversary of the crushing of the Prague Spring. Over the last few years, many state archives have opened their doors to historians. Today, a lot more background information about the occupation, the political setting and key players is available than only a few years ago. The history The focus is on the political events between January and August 1968, the escalating conflict between the reforms prompted by party leader Alexander Dubcek and the Kreml.