a change of government by force is a
Regime change Regime change can be precipitated by revolution or a coup d'état. The Russian Revolution, the 1962 Burmese coup and the 1990 collapse of communism in Eastern Europe (→ #Dissolution of the Eastern Bloc) are consummate examples.
Republic A republic (Latin: res publica) is a form of government in which the country is considered a "public matter", not the private concern or property of the rulers. The primary positions of power within a republic are not inherited. It is a form of government under which the head of state is not a monarch.[1][2][3]