Following the constituent assembly's adoption of a Soviet-modeled constitution, Yugoslavia formally became a federal socialist republic composed of six constituent nations, led by Josip Broz Tito. The move consolidated Tito's Partisan movement's wartime victory over royalists and occupying Axis forces into a lasting state structure that endured, with dramatic upheavals, until the 1990s.
Tito's path to power had run through one of Europe's most brutal guerrilla wars: his Communist-led Partisans fought Nazi occupiers, Italian forces, and rival Yugoslav factions simultaneously through World War II, emerging as the only resistance movement in occupied Europe to liberate its own capital largely without Soviet troops on the ground.
The new constitution abolished the monarchy of the exiled King Peter II and organized the country into six republics — Serbia, Croatia, Slovenia, Bosnia and Herzegovina, Macedonia, and Montenegro — an arrangement designed to balance the rival nationalisms that had torn Yugoslavia apart during the war.
Tito would soon break decisively with Stalin in 1948, steering Yugoslavia toward a distinctive non-aligned socialism that made it a bridge between East and West during the Cold War. The federal structure he built, however, contained the seeds of the ethnic fractures that would explode into war after Yugoslavia's disintegration in the 1990s.
Key people: Josip Broz Tito