Licinius was a Roman emperor from 308 to 324. He was suddenly elevated to the rank of augustus in 308 by his friend Galerius, who had become emperor. Galerius hoped to have him rule the West, but since Italy, Africa, and Spain were held by the usurper Maxentius, while Constantine reigned in Gaul and Britain, Licinius had to content himself with ruling Pannonia. When Galerius died in 311, Licinius took over Galerius’ European dominions. He married Constantine’s half-sister Constantia in 313 and in the same year defeated the Eastern emperor Maximinus at Tzurulum, pursuing him into Asia, where Maximinus died. Licinius thus added the entire eastern half of the empire to his dominion.
After a brief accord between the two augusti, Constantine forced Licinius to surrender the provinces of Pannonia and Moesia. There followed 10 years of uneasy peace in which Licinius built up his army and accumulated a huge reserve of treasure. In 324 Constantine defeated him at Adrianople and again at Chrysopolis (now Üsküdar, Tur.). Licinius surrendered, was exiled to Thessalonica, and was executed the next year on a charge of attempted rebellion.
