Battle of Pelekanon

Map of Ottoman expansion under Orhan

Date	June 10–11, 1329
Location	Near Nicomedia, Bithynia (present day: Maltepe,Turkey)
Result	Ottoman victory

Belligerents

Byzantine Empire

Ottoman Beylik

Commanders and leaders

Andronicus III
John Cantacuzene

Orhan I

Strength

~4,000 or less:
~2,000 soldiers from Constantinople, and something less than this number from Thrace.

~ 8,000

The Battle of Pelekanon also known by its Latinised form Battle of Pelecanum occurred on June 10–11, 1329 between an expeditionary force by the Byzantines led by Andronicus III and an Ottoman army led by Orhan I. The Byzantine army was defeated, with no further attempt made at relieving the cities in Anatolia under Ottoman siege.

By the accession of Andronicus in 1328, the Imperial territories in Anatolia had dramatically shrunk from almost all of the west of modern Turkey forty years earlier to a few scattered outposts along the Aegean Sea and a small core province around Nicomedia within about 150 km of the capital city Constantinople. Recently the Turks had captured the important city of Prusa (Bursa) in Bythinia. Andronicus decided to relieve the important besieged cities of Nicomedia and Nicaea and hopefully restore the frontier to a stable position. Together with the Grand Domestic John Cantacuzene, Andronicus led an army of about 4,000 men, which was the greatest he could muster along the Sea of Marmara towards Nicomedia. At Pelekanon, a Turkish army led by Orhan I had encamped on the hills to gain a strategic advantage and blocked the road to Nicomedia. On 10 June, Orhan sent 300 cavalry archers downhill to lure the Byzantines unto the hills, but these were driven off by the Byzantines, who were unwilling to advance further. Then belligerent armies engaged in a couple of indecisive clashes until nightfall and the Byzantine army prepared to retreat, but the Turks gave them no chance. Both Andronicus and Cantacuzene were lightly wounded, while rumors spread that the Emperor had either been killed or mortally wounded, resulting in panic. Eventually the retreat turned into a rout with heavy casualties on the Byzantine side. Cantacuzene led the remaining Byzantine soldiers back to Constantinople by sea.

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