Renamed the Kingdom of Yugoslavia on 3 October 1929, it was invaded by the Axis powers on 6 April 1941. In 1943, a Democratic Federal Yugoslavia was proclaimed by the Partisan resistance. In 1944, the king recognised it as the legitimate government, but in November 1945 the monarchy was abolished. Yugoslavia was renamed the Federal People's Republic of Yugoslavia in 1946, when a communist government was established. It acquired the territories of Istria, Rijeka, and Zadar from Italy. Partisan leader Josip Broz Tito ruled the country as president until his death in 1980. In 1963, the country was renamed again, as the Socialist Federal Republic of Yugoslavia (SFRY).
The constituent six socialist republics that made up the country were the SR Bosnia and Herzegovina, SR Croatia, SR Macedonia, SR Montenegro, SR Serbia, and SR Slovenia. Serbia contained two Socialist Autonomous Provinces, Vojvodina and Kosovo, which after 1974 were largely equal to the other members of the federation. After an economic and political crisis in the 1980s and the rise of nationalism, Yugoslavia broke up along its republics' borders, at first into five countries, leading to the Yugoslav Wars. From 1993 to 2017, the International Criminal Tribunal for the former Yugoslavia tried political and military leaders from the former Yugoslavia for war crimes, genocide and other crimes.
After the breakup, the republics of Serbia and Montenegro formed a reduced federation, the Federal Republic of Yugoslavia (FRY), which aspired to the status of sole legal successor to the SFRY, but those claims were opposed by the other former republics. Eventually, Serbia and Montenegro accepted the opinion of the Badinter Arbitration Committee about shared succession. In 2003 the Federal Republic of Yugoslavia was renamed to State Union of Serbia and Montenegro. The union peacefully broke up when Serbia and Montenegro became independent states in 2006, while Kosovo proclaimed its independence from Serbia in 2008.
The concept of Yugoslavia, as a single state for all South Slavic peoples, emerged in the late 17th century and gained prominence through the Illyrian Movement of the 19th century. The name was created by the combination of the Slavic words "jug" (south) and "slaveni" (Slavs). Yugoslavia was the result of the Corfu Declaration, as a project of the Serbian Parliament in exile and the Serbian royal Karađorđević dynasty, who became the Yugoslav royal dynasty.
The country was formed in 1918 immediately after World War I as the Kingdom of Serbs, Croats and Slovenes by union of the State of Slovenes, Croats and Serbs and the Kingdom of Serbia. It was commonly referred to at the time as the "Versailles state". Later, the government renamed the country leading to the first official use of Yugoslavia in 1929.