Ethnic hatred, religious rivalry, language barriers, and cultural conflicts plagued the Kingdom of the Serbs, Croats, and Slovenes (later renamed the Kingdom of Yugoslavia) from its inception. The question of centralization versus federalism bitterly divided the Serbs and Croats; democratic solutions were blocked and dictatorship was made inevitable because political leaders had little vision, no experience in parliamentary government, and no tradition of compromise. Hostile neighboring states resorted to regicide to disrupt the kingdom, and only when European war threatened in 1939 did the Serbs and Croats attempt a settlement. But that solution came too late to matter. The Kingdom of the Serbs, Croats, and Slovenes encompassed most of the Austrian Slovenian lands, Croatia, Slavonia, most of Dalmatia, Serbia, Montenegro, Vojvodina, Kosovo, the Serbiancontrolled parts of Macedonia, and Bosnia and Hercegovina. Territorial disputes disrupted relations with Italy, Austria, Hungary, Bulgaria, and Albania. Italy posed the most serious threat to Yugoslavia. Although it received Zadar, Istria, Trieste, and several Adriatic islands in the postwar treaties and took Rijeka by force, Italy resented not receiving all the territory promised under the 1915 Treaty of London. Rome subsequently supported Croatian, Macedonian, and Albanian extremists, hoping to stir unrest and hasten the end of Yugoslavia. Revisionist Hungary and Bulgaria also backed antiYugoslav groups.

The creation of Yugoslavia fulfilled the dreams of many South Slavic intellectuals who disregarded fundamental differences among twelve million people of the new country. The Serbs, Croats, and Slovenes had conflicting political and cultural traditions, and the South Slav kingdom also faced sizable nonSlav minorities, including Germans, Albanians, Hungarians, Romanians, and Turks, with scatterings of Italians, Greeks, Czechoslovaks, Slovaks, Ruthenians, Russians, Poles, Bulgars, Sephardic and Ashkenazic Jews, and Gypsies. The Orthodox, Roman Catholic, Islamic, Uniate, Jewish, and Protestant faiths all were well established and cut across ethnic and territorial lines. Besides the divisiveness of a large number of minority languages, linguistic differences also split the Serbs, Croats, Slovenes, and Macedonian Slavs. Many people regarded the new government and its laws as alien, exploitative, and secondary to kinship loyalties and traditions.

Data as of December 1990