Though Havel himself was never a Marxist, Czechs and Slovaks of his generation believed that Marx could be invoked to reform and humanize the country’s Soviet-style system. In the late 1960s, the Czechoslovak Party leadership believed that ‘socialism with a human face’ was possible. The Soviet leadership, Leonid Brezhnev in particular, was of another opinion. In August 1968, a Soviet (Warsaw Pact) invasion dispersed the loose association of Marxists, democrats, nostalgics and hippies whose proposals, texts, marches and happenings were collectively known as the Prague Spring.