Yugoslavia ("Land of the South Slavs") describes three separate political entities that existed on the Balkan Peninsula in Europe during most of the 20th century.

The Kingdom of Yugoslavia (December 1, 1918-April 17, 1941), also known as the First Yugoslavia, was a monarchy formed as the "Kingdom of Serbs, Croats and Slovenes" after World War I and re-named on January 6, 1929 by Alexander I of Yugoslavia. It was invaded on April 6, 1941 by the Axis powers and capitulated eleven days later.

The Second Yugoslavia (c.1943-), a socialist successor state to the Kingdom of Yugoslavia, existed under various names, including the "Democratic Federation of Yugoslavia (DFY)" (1943), the "Federal People's Republic of Yugoslavia (FPRY)" (1946), and the "Socialist Federal Republic of Yugoslavia (SFRY)" (1963). It disintegrated following the Yugoslav Wars, which led to the secession of most of the constituent elements of the SFRY.

The Federal Republic of Yugoslavia (FRY) (1992) was a federation on the territory of the two remaining republics of Serbia (including the autonomous provinces of Vojvodina and Kosovo and Metohija) and Montenegro. On February 4, 2003, the state transformed into a loose commonwealth called Serbia and Montenegro and officially abolished the name "Yugoslavia." On June 3 and June 5, 2006, Montenegro and Serbia respectively declared their independence, thereby ending the last remnants of the former Yugoslav federation.