With the introduction of multi-party system in 1990, individual republics elected their own heads of state, but the country's head of state continued to rotate among appointed representatives of republics and autonomous provinces until the country dissolved two years later.

The Kingdom of Serbs, Croats and Slovenes was created by the unification of the Kingdom of Serbia (the Kingdom of Montenegro had united with Serbia five days previously, while the regions of Kosovo, Vojvodina and Vardar Macedonia were parts of Serbia prior to the unification) and the provisional State of Slovenes, Croats and Serbs (itself formed from territories of the former Austria-Hungary) on 1 December 1918.

The royal family continued through his son (Alexander I) and his grandson (Peter II).

On 29 November 1943 an AVNOJ conference proclaimed the Democratic Federal Yugoslavia, while negotiations with the royal government in exile continued.

After the liberation of Belgrade on 20 October 1944, the Communist-led government on 29 November 1945 declared King Peter II deposed and proclaimed the Federal People's Republic of Yugoslavia.