Yugoslavia was a country in Southeastern and Central Europe for most of the 20th century. It came into existence after World War I in 1918 under the name of the Kingdom of Serbs, Croats and Slovenes 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 federal capital was Belgrade.

The Serbian royal House of Karađorđević became the Yugoslav royal dynasty. Yugoslavia gained international recognition on 13 July 1922 at the Conference of Ambassadors in Paris. The country was named after the South Slavic peoples and constituted their first union, following centuries in which the territories had been part of the Ottoman Empire and Austria-Hungary.

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