This article refers to an important period of history of Czechoslovakia in 1968. For the music festival of the same name, see Prague Spring International Music Festival.

The Prague Spring (Czech, Pražské jaro) was a period of political liberalization in Czechoslovakia starting January 5 1968, and running until August 20 of that year when the USSR and its Warsaw Pact allies (except for Romania) invaded the country.

The Czechs and Slovaks showed increasing signs of independence under the leadership of Alexander Dubček. Dubček's reforms of the political process inside Czechoslovakia, which he referred to as "Socialism with a human face", did not represent a complete overthrow of the old regime, as was the case in Hungary in 1956. However, it was still seen by the Soviet leadership as a threat to their hegemony over other Eastern European states.

The policy of the USSR to enforce Soviet-style governments among its satellite states, through military force if needed, became known as the Brezhnev Doctrine, named after Soviet leader Leonid Brezhnev, who was first to publicly declare it, although it was in use since Stalin's times. This doctrine remained in force until it was replaced by the Sinatra Doctrine under Mikhail Gorbachev in the 1980s.

The period of political liberalization in Czechoslovakia came to an end on August 20, when 200,000 Warsaw Pact troops and 5,000 tanks invaded the country. Criticism from the democratic countries was quite muted. Leftist writers such as Tariq Ali argue that this was because the western states saw the humane and democratic socialism espoused by the Czechoslovaks as being an even greater threat to capitalism than Soviet communism, which had largely been discredited by 1968. A more accepted explanation is that the West had already problems enough to keep it busy, in part because of the disruptive leftist agitation of May 1968, and the Vietnam War.

A decade later, the Prague Spring lent its name to an analogous period of Chinese political liberalization known as the Beijing Spring.

See also:

• Czechoslovakia: 1948 - 1968 (provides further details)