1918 Czechoslovakia becomes a republic.
1944 Soviet Union invades Czechoslovakia.
1948 Communist revolution in Czechoslovakia.
1950 Communist Czechoslovakia's ministry of foreign affairs asks nuncios of Vatican to leave the country.
1966 A Bulgarian plane with 82 people on board crashes near Bratislava, Czechoslovakia.
1968 Soviet Union-dominated Warsaw Pact troops invade Czechoslovakia, crushing the Prague Spring; on the same day, Nicolae Ceauşescu, leader of Communist Romania, publicly condemns the Soviet maneuver, encouraging the Romanian population to arm itself against possible Soviet reprisals.
1969 Student Jan Palach dies after setting himself on fire 3 days earlier in Prague's Wenceslas Square to protest the invasion of Czechoslovakia by the Soviet Union in 1968. His funeral turned into another major protest.
1989 Cold War: Velvet Revolution begins: In Czechoslovakia, a student demonstration in Prague is quelled by riot police. This sparks an uprising aimed at overthrowing the communist government (it succeeds on December 29).
1992 Václav Havel resigns as president of Czechoslovakia.