In 324, in the decisive final encounter between the two emperors, Roman forces loyal to Licinius (pictured) prevailed at the Battle of Chrysopolis, in Bithynia.
Licinius wins the Battle of ChrysopolisFollowing his catastrophic defeat at the Battle of the Hellespont, his rival Constantine had crossed over to Asia Minor, using a flotilla of light transports in order to avoid the enemy army, which, under the command of Licinius' newly appointed co-emperor Martinian, was guarding the coast at Lampsacus. Meanwhile Licinius had evacuated his garrison from Byzantium which joined his main army in Chalcedon on the Asiatic shore of the Bosporus. From there he also summoned Martinian's forces and a band of Visigothic auxiliaries, under their leader Aliquaca, to reinforce his principal army which had been depleted by its earlier defeat at the Battle of Adrianople.
Overconfident, Constantine seemingly eschewed any subtlety of manoeuvre, launching a single massive frontal assault on Licinius' troops but his forces were routed by them. Constantia, Constantine's half-sister and Licinius' wife, acted as intermediary, but no mercy was shown and Constantine was executed.