Their leader was Osman Ghazi (Osman I), who held the frontier land in western Asia Minor that was farthest north and closest to the Byzantines. Osman had become master of an area stretching from Eskishehir to the plains of Iznik and Brusa and had organized a fairly powerful principality.
When Osman I besieged around 1301, the Byzantines sent an army to raise the siege. The emep0ror depstahced against Osman a force of 2,000 men under the command of the Hetaereiarch Muzalon charged with the task relieving Iznik.
This army was defeated by Osman I in the summer of 1301 at Baphaeon, on the southeastern shores of the Sea of Marmara.
The local population was panic-stricken and started to leave, seeking shelter in the castle of Nicomedia.
This victory over the Byzantine imperial army made Osman prominent among other frontier lords the prospect of new conquest, booty and land attracted a wave of Turcoman warriors to be Ottoman principality.
Many other nomadic Turkish soldiers came to Konya, Osman’s capitol. They became known as beys, commanders of complements of fighters who were loyal to them, just as they in turn, were loyal to Osman.
In Ottoman tradition this victory is known as the victory won near Yalakova over the forces of the emperor during the siege do Iznik.
Battle of Baphaeon
