Soviet-led Warsaw Pact forces invade Czechoslovakia

On the night of August 20–21, 1968, military forces from the Soviet Union and four Warsaw Pact allies—Bulgaria, Hungary, Poland, and East Germany—invaded Czechoslovakia. The operation, codenamed ‘Danube’, involved an initial deployment of approximately 200,000 to 250,000 troops, eventually growing to an estimated 400,000 to 500,000 soldiers. This represented the largest military deployment in Europe since 1945.

The invasion effectively ended the ‘Prague Spring’, a democratic reform movement led by Alexander Dubček. The intervention was an application of the ‘Brezhnev Doctrine’, which asserted the right of the Soviet Union to intervene in other Eastern Bloc nations to prevent the abandonment of socialism.

Following the invasion, Dubček was arrested and taken to Moscow. Although he eventually returned to his position, he was stripped of significant power and replaced by Gustav Husak, a Moscow loyalist. This transition led to a period of ‘normalization’ characterized by a return to repressive communist policies and the suppression of liberal reforms.