Balkan state formed in 1918 after World War I. It included the previously independent kingdoms of Serbia and Montenegro and the southern Slavic territories formerly subject to the Austro-Hungarian Empire, including Dalmatia, Croatia -Slavonia, Slovenia , and Bosnia and Herzegovina .
The kingdom was ruled by the Serbian Karadjordjević dynasty . In 1929 King Alexander I sought to combat local nationalisms by proclaiming a royal dictatorship and renaming the state Yugoslavia . See also Serbia and Montenegro .