LICINIUS. Publius Flavius Galerius Valerius Licinianus Licinius, Roman emperor, of Dacian peasant origin, was born probably about 250 a.d., and was elevated after the death of Severus to the rank of Augustus by Galerius, his former friend and companion in arms, on November 11,307, receiving as his immediate command the provinces of Illyricum. On the death of Galerius in May 311, he shared the entire empire with Maximin, the Hellespont and the Thracian Bosphorus being their mutual boundary. In March 313 he entered into alliance with Constantine at Milan, and in the following month inflicted a decisive defeat on Maximin at Heraclea, with the result of establishing himself as master of the East, while Constantine (now his brother-in-law) was supreme in the West. In the following year his jealousy led him to entourage a treasonable enterprise on the part of Bassianus against Constantine. When his perfidy became known a civil war ensued, in which he was twice severely defeated—first near Cibalis in Pannonia (October 8, 314), and next in the plain of Mardia in Thrace; the outward reconciliation, which was effected in the following December, left Licinius in possession of Thrace, Asia Minor, Syria, and Egypt, but added numerous provinces to the Western empire. In 323 Constantine, tempted by the “advanced age and unpopular vices” of his colleague, anew declared war against him, and, having defeated his army at Adrianople (July 3, 323), succeeded in shutting him up within the walls of Byzantium. The defeat of the superior fleet of Licinius by Crispus, Constantine’s eldest son, compelled his withdrawal to Bithynia, where a last stand was made; the battle of Chrysopolis (September 18) finally issued in his submission and death.