The Emperor Constantine, founder of a new city at Byzantium and the first Roman emperor to espouse Christianity, steered a tortuous route to power. Born (c. 285) in the province of Moesia Superior (modern Serbia), he served with distinction in the east. His father, Constantinus, succeeded to the rank of Augustus in 305 and Constantine travelled to distant Britain to join him in his war against the Picts. When his father died at Eboracum (York) in July 306, his loyal soldiers immediately proclaimed Constantine Augustus. As master of western Europe, Constantine made his headquarters at Augusta Treverorum (Trier) for the next six years. Back in Rome the Senate had proclaimed Maxentius, Constantine’s brother-in-law, emperor. Conflict between the two imperial candidates culminated in 312 at the Battle of Milvain Bridge, a decisive victory for Constantine, who became sole ruler of the western half of the Empire. In 316 hostilities broke out with Licinius, the Eastern Emperor, in Pannonia and Thrace. When war erupted again in 324, Constantine fought, and won, two battles at Adrianopolis and Chrysopolis. Licinius was executed and Constantine became the master of the Roman world.
— OR —