In which country did Brezhnev participate in suppressing a popular rebellion?

Czechoslovakia

Brezhnev participated in suppressing a popular rebellion in Czechoslovakia.

Leonid Brezhnev, who led the Soviet Union from 1964 to 1982, introduced the concept of the Asian Collective Security system and played a prominent role in the détente phase of Soviet-American relations. His leadership was marked by significant international events, including the suppression of a popular rebellion in Czechoslovakia and the controversial invasion of Afghanistan. During his tenure, he sought to shape global security policies and played a key role in Soviet foreign affairs.