Constantine I, Byzantine Emperor (c.274-337). Flavius Valerius Constantinus, the first Christian emperor and the only emperor to execute his own son, was a dynamic general and reformer who made Christianity the empire's religion and founded a ‘New Rome’ which became Constantinople. Succeeding his father in 306 as emperor of Britain and Gaul, he destroyed his two eastern colleagues in a series of civil wars. Against the Emperor Maxentius in Italy, his wife's brother, he struck with an army drawn from the Rhine garrisons, quickly conquering the north and advancing on Rome. He won the decisive battle at the Milvian Bridge (28 October 312), driving Maxentius and his troops into the Tiber. This victory by ‘divine inspiration’, to quote the triumphal arch erected in Rome by the still pagan aristocracy, convinced Constantine that God had chosen him to unite both the empire and the church in his name. The fact that secular considerations also favoured this course of action is, of course, beside the point. The pagan Emperor Licinius, his sister's husband and his ally against Maxentius, was now driven out of the Danubian provinces in 317 and in 324, when Constantine broke their truce, defeated at Adrianople. Constantine then forced the Bosporus crossing and crushed Licinius near Chalcedon (modern Kadiköy) on 18 September 324.
Sole emperor at last, Constantine at once refounded Byzantium as an imperial headquarters (it was formally dedicated on 11 May 330). Licinius' ample treasury and the confiscated wealth of the pagan temples were lavished upon the imperial court, the army, and the now-established church. Immediately he found himself caught up in the fierce theological squabbles of the early church and summoned the first ecumenical council, at Nicaea in 325, which formulated the Trinitarian creed.
Throughout his reign Constantine energetically restored imperial authority on the Rhine and Danube frontiers. In the east, he was about to attack Persia when he died, leaving a costly war to his successors. The instrument of Constantine's military success was a new mobile army, the select comitatenses units under the emperor's immediate control, which supported the screen of frontier units (limitanei) and prevented any rebellion in the provinces. Officers and generals were now all professional soldiers, and the proportion of Germans and other non-Romans in the army increased. These military reforms, or rather this evolution which went back more than a century, gave new life to a tired empire.
Bibliography
- Barnes, Timothy D., Constantine and Eusebius (Cambridge, Mass., 1981).
- Cameron, Averil, The Later Roman Empire (London, 1993)
— Roger S. O. Tomlin
