In 1352, five decades following the establishment of the Ottoman principality, Süleyman Pasha captured the castle of Tzympe (Çimpe) on the Gallipoli penin-sula, thus beginning the period of permanent Ottoman conquest in the Balkans (İnalcık, 2005, 20). By 1365, the territorial expansion of the Ottomans extended beyond the borders of Bulgaria to the region bordering the lower Danube, mar-king the beginning of a significant geopolitical shift in the Balkans. With the re-sounding defeat of Balkan forces in the pivotal Battle of Kosovo in 1389, defense against the Ottomans became one of Hungary’s most urgent security concerns. To keep his rival away from his borders, King Sigismund of Luxembourg orga-nized cross-border campaigns into Ottoman lands with the aim of reconquering the Serbian fortresses captured by the Ottomans. These campaigns ended with temporary achievements; however, the defeat of the crusading army at Nicopolis in 1396 clearly proved that the Ottomans now were part of the Balkans. This fact is also confirmed by historical records, which show that after the Ottoman Em-pire’s heavy defeat at the hands of Timur in the Battle of Ankara, it did not suffer significant territorial losses in the Balkans, in contrast to the massive losses it suffered in Anatolia. (Kastritsis, 2007).