Po redaktohet VICKERS (paragraf)

=== The arrival of the Ottomans ===

During the late fourteenth century, disunity in the Balkans resulting from internal division and domestic squabbles was a prelude to the real danger that was materialising from the south-east. A new power now made its appearance as a factor in the history of Europe. The Ottoman Turks, an Asiatic people, had gradually worn away the weakened Byzantine Empire and in 1354 invaded the peninsula from Asia Minor. They began their inexorable trail of conquest by moving up through the Maritsa valley and capturing Macedonia in 1380. Lacking unity the various Balkan national rulers failed to recognize the problem and thus to stem the tide. The imminence and extent of the Ottoman threat had not been accurately estimated by either the Byzantines or the Balkan rulers, whose main efforts were absorbed in wars among themselves.

By 1370 the Serbian state was very different from the empire Dusan had left at the time of his death. Thessaly, Epirus and Albania had seceded entirely, and internal feuds between the various autonomous Slavic and Albanian lords had allowed the Ottomans, throughout the 1360s, to penetrate deep into Thrace with little opposition. They were unable to form a sufficiently strong and united coalition to fight the Ottomans when the latter confronted them on 26 September 1371 at the Battle of Marica, near Crnomen, where the Ottomans scored their greatest success up to that time. This battle, which heralded the decisive Ottoman invasion of Serbian-controlled lands, was far more significant in opening up the Balkans to the Turks and in weakening Serbian resistance than the later and more famous Battle of Kosovo (1389). Due partly to their unpreparedness, the Serbian forces were annihilated and in consequence the rest of Serbia disintegrated. Parts of it were grabbed by the still feuding warlords who, distrusting each other, struggled to fill the vacuums created by the collapse of central power.

The Battle of Marica made the disintegration of the rest of Serbia easier; the central government, such as it was, lost the bulk of its forces in the battle, while the nobles who had not fought retained their forces unimpared. In 1386 the Ottomans invaded Serbia and captured the key communication `crossroads' of Nis. In the ensuing peace treaty the Serbs agreed to pay the Ottomans an annual tribute and provide 1,000 mercenaries for the Ottoman army. At last, and too late, the Balkan states realised that they had to unite against the Ottoman threat. The Bosnian king (Tvrtko) sent a detachment of soldiers to aid the Serbs, and in the fastness of Montenegro a combined force of Albanians and Serbs utterly defeated the Ottoman army. Its leader Sultan Murad I (1362-89), then absent in Asia Minor, swore revenge. He dashed back to Europe and assembled an enormous army to march against the Serbs.