The State of Slovenes, Croats and Serbs was a political entity that was constituted in October 1918, at the end of World War I, by Slovenes, Croats and Serbs (Prečani) residing in what were the southernmost parts of the Austro-Hungarian Empire. Although internationally unrecognised, this was the first incarnation of a Yugoslav state founded on the Pan-Slavic ideology. Thirty-three days after it was proclaimed, the state joined the Kingdom of Serbia to form the Kingdom of Serbs, Croats and Slovenes.

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