The Prague Spring was a period of political liberalization in Czechoslovakia during 1968 led by Alexander Dubček. He implemented reforms to democratize the government and open the country to Western influence, which was initially popular among citizens accustomed to censorship and oppression under the previous Soviet-backed regime. However, the Soviet Union grew uneasy with Dubček's reforms and led a military invasion in August 1968 to suppress the Prague Spring and reinstate authoritarian control, replacing Dubček as leader.