This Spring marks the 40th anniversary of the Prague Spring–a domestic, Czech-led liberalization and democratization movement in the former Czechoslovakia–and the subsequent Soviet military invasion of that former communist state. As Czechs sang and wrote their way towards a regime Czechs would describe as “Communism with a human face”, Leonid Brezhnev–the leader of the Soviet Union–rolled Soviet tanks onto the streets of Prague to put an end to Alexander Dubcek’s reforms. This was the first concrete foreign policy manifestation of the “combating of anti-socialist forces,” which came to be known as the Brezhnev Doctrine.
Euronews has an interesting report on the commemoration of the Prague Spring, which has been uploaded to youtube. I encourage you to take a look.