First Yugoslavia

Kingdom of Serbs, Croats and Slovenes (1918–1929) Kingdom of Yugoslavia (1929–1945)
1918–1945
Flag Coat of arms
Motto "Jedan narod, jedan kralj, jedna država"  (Latin) Један народ, један краљ, једна држава  (Cyrillic) "One people, one king, one country"
Anthem National Anthem of the Kingdom of Yugoslavia
Location and extent of the Kingdom of Yugoslavia in Europe during the 1930s
Capital		Belgrade
Languages		Official language: Serbo-Croato-Slovenea
Government		Constitutional monarchy (1918–1929, 1934–1945) Absolute monarchy (1929–1934)
King
•	1918–1921	Peter I
•	1921–1934	Alexander I
•	1934–1945	Peter IIb
Prince Regent
•	1918–1921	Prince Alexander
•	1934–1941	Prince Paul
Prime Minister
•	1918–1919 (first)	Stojan Protić
•	1945 (last)	Josip Broz Tito
Legislature		National Assembly
•	Upper house	Senate
•	Lower house	Chamber of Deputies
Historical era		Interwar period · World War II
•	Creation	1 December 1918
•	Vidovdan Constitution	28 June 1921
•	Dictatorship	6 January 1929
•	Axis invasion	6 April 1941
•	Democratic Federative Yugoslavia	4 December 1943
•	Treaty of Vis	2 November 1945
•	Abolition of monarchy	29 November 1945
Area
•	1918	247,542 km² (95,577 sq mi)
Population
•	1918 est.	12,017,323
Density		48.5 /km²  (125.7 /sq mi)
•	1931 est.	13,934,038
Density		56.3 /km²  (145.8 /sq mi)
Currency		Yugoslav krone (1918–1920) Royal Yugoslav dinar (1920–1945)
Preceded by Succeeded by State of Slovenes, Croats and Serbs Kingdom of Serbia Kingdom of Montenegro Socialist Federal Republic of Yugoslavia
Today part of		Bosnia and Herzegovina  Croatia  Kosovo  Macedonia  Montenegro  Serbia  Slovenia
a.	Declared in both of the country's constitutions (1921 and 1931), srpsko-hrvatsko-slovenački is also translated as Serbo-Croato-Slovene or Serbocroatoslovenian, despite Serbo-Croat and Slovene being separate languages.
b.	Peter II, still underage, was brought to power by a military coup. Shortly after his accession, Yugoslavia was occupied by the Axis and the young King went into exile. In 1944, he accepted the formation of Democratic Federal Yugoslavia, along with a temporary vacancy in the position of head of state. He was formally deposed by the Yugoslav parliament in 1945.

The Kingdom of Yugoslavia (Serbo-Croatian: Kraljevina Jugoslavija, Serbian Cyrillic: Краљевина Југославија, "Kingdom of South Slavia) was a state in Southeast Europe and Central Europe, that existed during the interwar period (1918–1939) and first half of World War II (1939–1943). It 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, while the regions of Kosovo, Vojvodina and Vardar Macedonia were parts of Serbia prior to the unification. For its first eleven years of existence, the Kingdom was officially called the Kingdom of Serbs, Croats and Slovenes, but the term "Yugoslavia" was its colloquial name from its origins. The official name of the state was changed to "Kingdom of Yugoslavia" by King Alexander I on 3 October 1929.

The state was ruled by the Serbian dynasty of Karađorđević, which previously ruled the Kingdom of Serbia under Peter I from 1903 (after the May Overthrow) onwards. 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. His cousin Paul ruled as Prince regent until 1941, when Peter II would come of age. The royal family flew to London the same year, prior to the country being invaded by the Axis powers.