Serbs migrated to the territories of modern Kosovo in the 7th century but did not fully incorporate them into the Serbian realm until the early 13th century. The Serbian defeat at the Battle of Kosovo in 1389 led to five centuries of Ottoman rule during which large numbers of Turks and Albanians moved to Kosovo. By the end of the 19th century, Albanians replaced the Serbs as the dominant ethnic group in Kosovo. Serbia reacquired control over Kosovo from the Ottoman Empire during the First Balkan War (1912). After World War II (1945), the government of the Socialist Federal Republic of Yugoslavia led by Josip TITO reorganized Kosovo as an autonomous province within the constituent republic of Serbia. Over the next four decades, Kosovo Albanians lobbied for greater autonomy, and Kosovo was granted the status almost equal to that of a republic in the 1974 Yugoslav Constitution. Despite the legislative concessions, Albanian nationalism increased in the 1980s leading to nationalist riots and calls for Kosovo's independence. Serbs in Kosovo complained of mistreatment and Serb nationalist leaders, such as Slobodan MILOSEVIC, exploited those charges to win support among Serbian voters many of whom viewed Kosovo as their cultural heartland. Under MILOSEVIC's leadership, Serbia instituted a new constitution in 1989 that drastically curtailed Kosovo's autonomy. Kosovo Albanian leaders responded in 1991 by organizing a referendum that declared Kosovo independent from Serbia. The MILOSEVIC regime carried out repressive measures against the Albanians in the early 1990s as the unofficial government of Kosovo, led by Ibrahim RUGOVA, tried to use passive resistance to gain international assistance and recognition of its demands for independence. In 1995, Albanians dissatisfied with RUGOVA's nonviolent strategy created the Kosovo Liberation Army and launched an insurgency. In 1998, MILOSEVIC authorized a counterinsurgency campaign that resulted in massacres and massive expulsions of ethnic Albanians by Serbian military, police, and paramilitary forces. The international community tried to resolve the conflict peacefully, but MILOSEVIC rejected the proposed international settlement - the Rambouillet Accords - leading to a three-month NATO bombing of Serbia beginning in March 1999, which forced Serbia to withdraw its military and police forces from Kosovo in June 1999. UN Security Council Resolution 1244 (1999) placed Kosovo under a transitional administration, the UN Interim Administration Mission in Kosovo (UNMIK), pending a determination of Kosovo's future status. Under the resolution, Serbia's territorial integrity was protected, but it was UNMIK that assumed responsibility for governing Kosovo. In 2001, UNMIK promulgated a Constitutional Framework, which established Kosovo's Provisional Institutions of Self-Government (PISG). In succeeding years UNMIK increasingly devolved responsibilities to the PISG. A UN-led process began in late 2005 to determine Kosovo's future status. Negotiations held intermittently between 2006 and 2007 on issues related to decentralization, religious heritage, and minority rights failed to yield a resolution between Serbia's willingness to grant a high degree of autonomy and the Albanians' call for full independence for Kosovo. On 17 February 2008, the Kosovo Assembly declared its independence from Serbia. Its languages are: Albanian (official), Serbian (official), Bosniak, Turkish, and Roma