Czechoslovakian politician Alexander Dubček as first secretary of the Communist party in 1968 introduced reforms and pursued an independent foreign policy; in August 1968, Soviet authorities sent tanks into Prague, arrested him, and forced him to resign.
https://en.wikipedia.org/wiki/Alexand... Czechoslovakian politician Alexander Dubček as first secretary of the Communist party in 1968 introduced reforms and pursued an independent foreign policy; in August 1968, Soviet authorities sent tanks into Prague, arrested him, and forced him to resign.