Ber·lin /ˌbɜːˈlɪn◂ $ ˌbɜːr-/ the capital city of Germany. Berlin was divided into East Berlin and West Berlin after World War II. East Berlin was controlled by the communists. Berlin became a united city again when the Berlin Wall was destroyed in 1989 and in 1990 the German Democratic Republic (East Germany) and the Federal Republic of Germany (West Germany) became one country again.