Battle of Bapheus

The Battle of Bapheus occurred on 27 July 1302, between an Ottoman army under Osman I and a Byzantine army under George Mouzalon. The battle ended in a crucial Ottoman victory, cementing the Ottoman state and heralding the final capture of Byzantine Bithynia by the Turks.

Osman I had succeeded in the leadership of his clan in c. 1282, and over the next two decades launched a series of ever-deeper raids into the Byzantine borderlands of Bithynia. By 1301, the Ottomans were besieging Nicaea, the former imperial capital, and harassing Prusa. The Turkish raids also threatened the port city of Nicomedia with famine, as they roamed the countryside and prohibited the collection of the harvest .

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