Since the middle of the 14th century, the Ottoman threat was looming in the Balkans, as the Ottomans defeated the various Christian principalities, whether Serb, Bulgarian or Greek. After the Ottoman victory in the Battle of Maritsa in 1371, most of Macedonia accepted vassalage to the Ottomans and by the end of the 14th century the Ottoman Empire gradually annexed the region. The final Ottoman capture of Thessalonica (1430) was seen as the prelude to the fall of Constantinople itself. Macedonia remained a part of the Ottoman Empire for nearly 500 years, during which time it gained a substantial Turkish minority. Thessaloniki later become the home of a large Sephardi Jewish population following the expulsions of Jews after 1492 from Spain.