The Balkans

ollowing their permanent settlement in Thrace, the Ottomans began to threaten Macedonia directly. The Turkish danger, now common to both the Serbs and Byzantines, brought them closer together. The Serbian ruler of the region of Serres, John Ugljesa, in an endeavour to approach the Byzantines, went so far as to condemn Stefan Dusan's policies and the establishment of an independent Serbian Patriarchate. Moreover, he recognised the jurisdiction of the Patriarchate of Constantinople over his domains and even volunteered to support Byzantium financially.

Finally, however, only Ugljesa's brother, King Vukasin, made common cause with him. Together they confronted the Turkish army at Cernomen, on the river Hebros, 35 kilometres west of Adrianople, where they were routed on 26 September 1371. The Hebros ran red with the blood of the Serbian soldiers, while both their rulers were also killed.

The defeat of the Serbs at Cernomen had disastrous consequences for the states of the Balkan peninsula. The Serbs and the Bulgars recognised the Turkish suzerainty and were forced to pay tribute and to offer military service to the Sultan. When John V returned from Rome where he had gone to ask for help against the Turks in exchange for the union of the Churches (1369-71), disheartened by the failure of his journey to the West and the victory of the Turks at Cernomen, he thought it wise to recognise the suzerainty of the Sultan in his turn (1372). What is more, he was obliged to accompany the latter on his military expeditions. Thus, the two Christian states of the Balkans (Serbia and Bulgaria) as well as the once mighty Byzantine Empire, became, for the first time, vassals of the Turks.