Postwar Nationalism, Ethnic Conflict, and Atrocities

Yugoslavia held six republics together under Tito's one-party rule and his own authority as a unifying figure. He died in 1980. Communism across eastern Europe collapsed by 1989 to 1991. Without Tito or communist ideology to hold the country together, politicians in each republic turned to ethnic nationalism to build support, especially Serbian leader Slobodan Milosevic. The problem was that Tito's internal borders had been drawn to balance power among Serbs, Croats, Slovenes, Bosniaks, and others, not to separate them into clean ethnic territories. Bosnia especially was a patchwork of intermixed Serb, Croat, and Bosniak communities living in the same towns and regions.

When republics like Slovenia, Croatia, and Bosnia declared independence between 1991 and 1992, Serbia and Serb militias tried to carve out and hold territory with Serb majorities, including land inside Bosnia's borders. Because the populations were mixed rather than separated, the only way to make territory ethnically Serb was to remove everyone else: ethnic cleansing, meaning forced expulsion, and at Srebrenica in 1995, mass killing of Bosniak men and boys. War in Bosnia ran from 1992 to 1995 and displaced roughly two million people, redrawing who lived where by force rather than by negotiation.

This was not a new pattern. After 1945, millions of ethnic Germans were expelled from Poland, Czechoslovakia, and other eastern territories as borders shifted westward, leaving those states far more ethnically uniform than before the war. Yugoslavia's breakup shows the same logic returning in miniature, decades later: when political order collapses, mismatched borders and populations get forcibly resolved through displacement.