Probably the first local ruler to become aware of the impending Ottoman threat, Momchil unsuccessfully pleaded with the emperors of Bulgaria and Byzantium for help. Even though his troops continued the resistance in the Eastern Rhodopes, in May 1345 the Turks led by Umur Beg marched from Asia Minor and devastated Bulgarian territories driving away people and livestock. Soon after, on 7 July 1345, Ottoman forces under Umur Beg defeated Momchil's army in the battle of Peritor near his capital Xanthi. Sources attest that the independent ruler perished in the battle without leaving asuccessor, and with little political will or leadership left to counter the Ottoman invasion.