Gw mau tau Strategic context dari Pertempuran Bapheus

Osman I had succeeded in the leadership of his clan in ca. 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 Prussa. The Turkish raids also threatened the port city of Nicomedia with famine, as they roamed the countryside and prohibited the collection of the harvest.

In the spring 1302, Emperor Michael IX (r. 1294–1320) launched a campaign which reached south up to Magnesia. The Turks, awed by his large army, avoided battle. Michael sought to confront them, but was dissuaded by his generals. The Turks, encouraged, resumed their raids, virtually isolating him at Magnesia. His army dissolved without battle, as the local troops left to defend their homes and the Alans too left to rejoin their families in Thrace. Michael was forced to withdraw by the sea, followed by another wave of refugees.