Your Day in the Ancient Greek World

September 18

September 18 in ancient Greece is represented in our source-audited archive by one verified record dated AD 324. The entry below connects this calendar date with its surviving historical evidence and context.

Across the centuries

On This Day

  1. AD 324

    Event That Shaped History

    Chrysopolis, opposite Byzantium Warfare & Strategy High

    Constantine Defeats Licinius at Chrysopolis

    On September 18, AD 324, Constantine defeated Licinius at Chrysopolis across the Bosporus from Byzantium. The victory established Constantine as sole ruler of the Roman Empire and directly preceded the transformation of Byzantium into the imperial capital that became Constantinople. The battle therefore sits at a major turning point in the history of the Greek-speaking eastern Mediterranean.

    Sources

    Primary evidence

    • Late Roman historical sources for Constantine's war with Licinius

    Modern scholarship

    • The Cambridge Companion to the Age of Constantine
    • Modern scholarship on Constantine and Licinius

    Public links