Editor's note: Politicians jump in where historians fear to tread. To help readers understand the background to the current conflict, WORLD prepared this survey of rivalries. Not long ago, as ethnic memories are measured, Serbian forces, outnumbered and outmaneuvered by a vastly stronger foreign force, suffered a bloody defeat in Kosovo. But the year was 1389, not 1999, and the outside force was the Turkish-led Ottoman Empire, not the American-led NATO alliance. That battle, which lives on in Serb lore as a rough equivalent to what Pickett's Charge is for the American South, has helped make Kosovo an important part of Serb national identity. But Kosovo's ethnic Albanians also view the province through the emotional lens of ancestral allegiance. They claim to be the descendants of the ancient Illyrians, Kosovo's first inhabitants. That claim from Roman Empire days fuels demands for an independent Kosovar state. Language and religious traditions are also fault lines. Serbs and Albanians speak unrelated languages and espouse religions (Eastern Orthodoxy and Islam, respectively) historically at loggerheads. But this is hardly the only conflict in the region. Get a scorecard ready, because in addition to the Serbs and Albanians, the Balkan stew consists of Croats, Slovenes, Montenegrins, Bosnian Muslims, and Macedonians. Each has historically despised most of the others, wanted independence from the others, and sought to expand its influence in the area. Except for the Albanians, they are all Slavs descended from tribes that migrated to the peninsula during the seventh century. Over time, these competing tribes became nations. The Roman Catholic/Byzantine split in 1054 added religious differences to the mix. Slovenes and Croats sided with Rome, while Serbs, Bosnians, Macedonians, and Montenegrins joined the Orthodox Church. Croatia, conquered by Hungary in 1102, became part of the Austro-Hungarian Empire, while Serbia remained independent until its legendary battle with the Ottoman Turks. The Turks brought Islam with them to the Balkans and converted some of the peninsula's inhabitants; the converts' descendants are today's Bosnian Muslims. Depending on whom you ask, originally they were either Croat, Serb, or both. (Ethnic Albanians are the only other remaining Muslims in the region today.) After five centuries, the Ottoman Empire began to disintegrate and the West stepped in. The Congress of Berlin gave Bosnia to the Austro-Hungarian Empire in 1878, and declared Serbia and Montenegro to be independent nations. In 1912, during the First Balkan War, Serbia, Montenegro, Greece, and Bulgaria pushed the Turks out of the Balkans completely. That was the good news. The bad news was that the dispute over Kosovo began. Both the Serbs and the new Albanian state claimed Kosovo. The West, wanting to strengthen Serbia as a counter-weight to Russian and Turkish claims in the southern Balkans, awarded it the coveted province, leaving about a third of the Albanian population living outside Albania. Then came World War I, which began in 1914 after a Serb nationalist (who wanted Bosnia given to Serbia) assassinated Archduke Franz Ferdinand of the Austro-Hungarian royal family. Some say the major European powers stumbled into war; others say the assassination was an excuse to go to war. Either way, the result was catastrophe. After the war, Serbia, Bosnia, Croatia, and Slovenia joined to form the "Kingdom of Serbs, Croats, and Slovenes," which later became simply Yugoslavia (or "South Slavs"). This lasted until World War II, when the Nazis sponsored in the region a brutal Croatian regime that killed hundreds of thousands of Serbs, Jews, and Gypsies. After World War II, iron-fisted stability came to the region as Communist strongman Josip Broz Tito crushed various nationalist movements and recreated Yugoslavia, this time with Slovenia, Croatia, Macedonia, Montenegro, and Serbia. Tito broke with the Soviets in 1948; with Western help Yugoslavia remained intact until 1990. That year Yugoslavia held its first free elections, which brought nationalists to power throughout the region. Nationalist governments in Slovenia, Croatia, and Macedonia declared independence in 1991. Slovenia left peacefully, but Croatia had to fight a six-month war, with 10,000 killed, to gain its independence. NATO peacekeepers kept Macedonia safe. In 1992 Bosnia, under a Muslim government, declared independence. Since Serbs and Croats in Bosnia wanted to remain in their respective nations, a three-way war began. Hundreds of thousands were killed, but a 1995 conference in Dayton, Ohio, created a fragile peace. Now Yugoslavia consists only of Serbia, which includes Kosovo, and Montenegro. Before the bombing and mass displacements started, about 90 percent of Kosovo's 2.2 million people were ethnic Albanians; 10 percent were Serbs. Both claim the province is rightfully theirs.