Constantine the Great

Constantine I, also known as Constantine the Great, was a Roman emperor from 306 to 337. Born in Naissus, Dacia Mediterranea, he was the son of Flavius Constantius, an Illyrian army officer who became one of the four emperors of the Tetrarchy. His mother, Helena, was Greek and of low birth. Constantine served with distinction under emperors Diocletian and Galerius campaigning in the eastern provinces against barbarians and the Persians, before being recalled west in 305 to fight under his father in Britain. After his father's death in 306, Constantine was acclaimed as emperor by the army at Eboracum (York). He emerged victorious in the civil wars against emperors Maxentius and Licinius to become sole ruler of the Roman Empire by 324.