Battle of Chrysopolis

The Battle of Chrysopolis was fought on 18 September 324 at Chrysopolis , near Chalcedon , between the two Roman emperors Constantine I and Licinius. The battle was the final encounter between the two emperors. After his navy's defeat in the Battle of the Hellespont, Licinius withdrew his forces from the city of Byzantium across the Bosphorus to Chalcedon in Bithynia. Constantine followed, and won the subsequent battle. This left Constantine as the sole emperor, ending the period of the Tetrarchy.

The navy of Licinius had suffered a catastrophic defeat at the Battle of the Hellespont. His admiral, Abantus, had been outfought by Constantine's son, the caesar Crispus, despite the latter's distinctly smaller fleet. Following this naval victory, Constantine crossed over to Asia Minor. He used a flotilla of light transports he had ordered to be built on the Bosphorus in order to avoid the enemy army, which, under the command of Licinius' newly appointed co-emperor Martinian, was guarding the coast at Lampsacus on the Hellespont.

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