On 18th September 324AD, the two roman emperors – Constantine I and Licinius – fought in the Battle of Chrysopolis.
After his navy’s defeat in the Battle of the Hellespont, Licinius withdrew his forces from the city of Byzantium. They crossed 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.
Licinius evacuates Byzantium
The navy of Licinius 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 smaller fleet.
Following the destruction of his naval forces, Licinius evacuated the garrison of Byzantium. Then he joined his main army in Chalcedon on the Asiatic shore of the Bosphorus. With depleted forces after the Battle of Adrianpole, Licinius summoned Martinian’s forces and a band of Visigothic auxiliaries, under their leader Aliquaca as reinforcements. It is not clear whether Martinian’s forces reached Licinius before September 18, when the Battle of Chrysopolis took place.
Battle Of Chrysopolis
Constantine’s army landed at the Sacred Promontory and marched southward towards Chalcedon. Licinius moved his army a few miles north towards Chrysopolis. Constantine’s army reached the environs of Chrysopolis before the forces of Licinius.
Before the battle, Constantine – a Christian – took to his tent to seek divine guidance, and decided to take the initiative. His army fought under the labarum, his talismanic standard. Liciunius, on the other hand, had prominent images of the pagan gods of Rome displayed in his battle lines.
Constantine appears to have launched a single frontal assault on the troops of Licinius. His was the decisive victory in what was a very large-scale battle. According to the historian Zosimus, “There was great slaughter at Chrysopolis.”
Licinius was reported to have lost 25,000 to 30,000 dead on the battle field. Thousands more broke ranks and fled. Licinius, himself, managed to escape and gather about 30,000 of his surviving troops at the city of Nicomedia.
Death of Licinius
Licinius recognised the futile situation he was in and threw himself on Constantine’s mercy. His wife, Constantia – half-sister of Constantine – acted as intermediary. Initially, Constantine listened to his sister and spared the life of Licinius.
However, the army pressed for the death of Licinius, stating treasonable actions. Constantine, therefore, ordered his execution. A year later, Licinius II – Constantine’s nephew – also met the executioner, and his name was expunged from official inscriptions.
Sole emperor with eponymous capital
With Licinius’s deafeat, Constantine became the sole emperor of the Roman Empire. This was the first time since the elevation of Maximian to the status of Augustus by Diocletian in April 286.
After his conquest of the eastern Roman Empire, Constantine gave the east its own capital. He renamed the city of Byzantium as Constantinopolis.
The statue of Constantine is at Palazzo dei Conservatori, Rome