A combined army of Serbs, Albanians, and Hungarians, led by the Serb knez, or prince, Lazar Hrebeljanovic, and including a large Bosnian contingent sent by Tvrtko, meets Murad's forces in battle on St. Vitus' Day (Vidovdan), June 28 (June 15, Old Style), 1389, on the Kosovo Polje ("Field of Blackbirds") near Pristina.

Victory appears at first to be on the side of the Serbs when Murad is killed by a Serbian noble, Miloš Obilić (or Kobilic), who had made his way into the Turkish camp on the pretext of being a deserter and forced his way into Murad's tent and stabbed him with a poisoned dagger.

Murad's twenty-nine-year-old son Bayezid quickly quells the confusion, and succeeds in surrounding the Serbs and inflicting a crushing defeat on their army.

Lazar is taken prisoner and executed; the Serbs are forced to pay tribute to the Turks and promise to do military service in the Ottoman army.

The defeat of the Serbs at the Battle of Kosovo seals the fate of the entire Balkan Peninsula, but will become hallowed in several great heroic ballads.

The vision of Lazar on the eve of the battle, the alleged betrayal by the Bosnian Vuk Brankovic, the killing of Murad by Serbian knight Miloš Obilić, the succor brought to the wounded on the battlefield by the Maid of Kosovo—these and other stories will be immortalized in Serbian folk literature.