TRENDEAtlas of the Sultans · Wars, battles and treaties
Battle · 1302
The Battle of Bapheus occurred on 27 July 1299, between an Ottoman Turkish army under Osman I and a Eastern Roman (Byzantine) army under Georgios Mouzalon. The battle ended in a crucial Ottoman victory, cementing the Ottoman state and heralding the final capture of Eastern Roman (Byzantine) Bithynia by the Ottoman Turks.
| Date | 27 July 1299 |
|---|---|
| Location | Koyunhisar plain |
| Result | Ottoman victory |
| Territorial changes | Koyunhisar and castles near Bursa annexed by the Ottomans |
| Belligerents | Eastern Roman (Byzantine) Empire | Ottoman Beylik Loyal Turkmen tribes |
|---|---|---|
| Commanders | Georgios Mouzalon | Osman Gazi Köse Mihal |
| Strength | ~2,000 | ~5,000 |
Bapheus was the first major victory for the nascent Ottoman Beylik, and of major significance for its future expansion: the Eastern Roman (Byzantine)s effectively lost control of the countryside of Bithynia, withdrawing to their forts, which, isolated, fell one by one. After this battle the countryside of Bithynia was left practically defenceless so Osman used this opportunity to conquer the castle of Koyunhisar and the coastal town of Gemlik. The Eastern Roman (Byzantine) defeat also sparked an exodus of the Christian population from the area into the European parts of the empire, further altering the region's demographic balance.
Took place during the reign of Osman I (1299–1324). Osman I
The atlas records this territorial change for the year:
Text: Wikipedia (CC BY-SA 4.0), adapted for the atlas.