a former country in SE Europe, on the Adriatic: established in 1918 from the independent states of Serbia and Montenegro, and regions that until World War I had belonged to Austria-Hungary (Croatia, Slovenia, and Bosnia-Herzegovina); the name was changed from Kingdom of Serbs, Croats, and Slovenes to Yugoslavia in 1929; German invasion of 1941–44 was resisted chiefly by a Communist group led by Tito, who declared a people's republic in 1945; it became the Socialist Federal Republic of Yugoslavia in 1963; in 1991 Slovenia, Croatia, Bosnia and Herzegovina, and Macedonia declared independence; Serbia and Montenegro formed the Federal Republic of Yugoslavia, subsequently (2003) replaced by the Union of Serbia and Montenegro (dissolved 2006)