The Kingdom of Yugoslavia (Serbo-Croatian: Краљевина Југославија / Kraljevina Jugoslavija; Slovene: Kraljevina Jugoslavija) was a state in Southeast Europe and Central Europe that existed from 1918 until 1941, during the interwar period and beginning of World War II. From 1918 to 1929, it was officially called the Kingdom of Serbs, Croats and Slovenes (Serbo-Croatian: Краљевина Срба, Хрвата и Словенаца / Kraljevina Srba, Hrvata i Slovenaca; Slovene: Kraljevina Srbov, Hrvatov in Slovencev), but the term “Yugoslavia” (literally “Land of Southern Slavs“) was its colloquial name due to its origins. The official name of the state was changed to “Kingdom of Yugoslavia” by King Alexander I on 3 October 1929.
The preliminary kingdom was formed in 1918 by the merger of the provisional State of Slovenes, Croats and Serbs (itself formed from territories of the former Austro-Hungarian Empire) with the formerly independent Kingdom of Serbia. The Kingdom of Montenegro had united with Serbia five days previously, whereas the regions of Kosovo, Vojvodina, Vardar Macedonia and most of Bosnia were parts of Serbia prior to the unification.
The state was ruled by the Serb dynasty of Karađorđević, which previously ruled the Kingdom of Serbia under Peter I from 1903 (after the May Overthrow) onward. Peter I became the first king of Yugoslavia until his death in 1921. He was succeeded by his son Alexander I, who had been regent for his father. He was known as “Alexander the Unifier” and he renamed the kingdom “Yugoslavia” in 1929. He was assassinated in Marseille by Vlado Chernozemski, a member of the Internal Macedonian Revolutionary Organization (IMRO), during his visit to France in 1934. The crown passed to his then-still under-aged son Peter. Alexander’s cousin Paul ruled as Prince regent until 1941, when Peter II came of age. The royal family flew to London the same year, prior to the country being invaded by the Axis powers. Wikipedia
Photography Yugoslavia 1920