CONSTANTINE I., FLAVIUS VALERIUS AURELIUS, surnamed the great, a Roman emperor, was born 272 or 274 A.D., at Naissus, in Moesia. He was the eldest son of Constantius Chlorus, and first distinguished himself by his military talent under Diocletian, in that monarch's famous Egyptian expedition, 296; subsequently he served under Galerius in the Persian war. In 305 the two Emperors, Diocletian and Maximian abdicated, and were succeeded by Constantius Chlorus and Galerius.
Galerius, who could not endure the brilliant and energetic genius of Constantine, took every means of exposing him to danger, and it is believed that this was the period when he acquired that mixture of reserve, cunning, and wisdom, which was so conspicuous in his conduct in after years.
At last Constantine fled to his father, who ruled in the West. Constantius died July 25th, 306, having proclaimed his son Constantine his successor. He was opposed by Maxentius whom he three times defeated, first near Turin, then under the walls of Verona, and finally in the vicinity of Rome, 28th October, 312, Maxentius himself being drowned in an attempt to escape across the Tiber.
Constantine was now sole Emperor of the West. Similarly, by the death of Galerius in 311, and of Maximin in 313, Licinius became sole Emperor of the East.
In 314, a war broke out between the two rulers, in which Licinius had the worst, and was forced to conclude a peace by the cession of Illyricum, Parenovia, and Greece.
Constantine gave Licinius his sister Constantina in marriage, and for the next nine years devoted himself vigorously to the correction of abuses in the administration of the laws, to the strengthening of the frontiers of his Empire, and to the chastising of the barbarians, who learned to fear and respect his power.
In 323, he renewed the war with Licinius, whom he defeated, and ultimately put to death.
Constantine was now at the summit of his ambition, the sole governor of the Roman world. He chose Byzantium for his Capital, and in 330 solemnly inaugurated it as the seat of government, under the name of Constantinople or City of Constantine. In 324, he committed a deed that has thrown a dark shade over his memory. He had a gallant and accomplished son, named Crispus, who was exceedingly popular, and him and Constantina and others he put to death on a charge of treason. Niebuhr shows that it was not unlikely Crispus cherished ambitious desires. Next year occurred the great Council of Nice. Constantine sided with the Orthodox Fathers. As yet he was a pagan, but his sense of justice, and his conviction of the growing importance of the Christians, both as a moral and political element in the life of the Empire, had from the very first induced him to protect them. As early as 313 he had granted them toleration, and since then continued to favor them more and more decidedly. During the latter years of his life, Christianity became the state religion, the pagan temples were closed, and sacrifices forbidden. Yet it was only a short time before his death which occurred 22nd July, 337, that he would allow himself to be baptized.
As an Emperor Constantine ranks very high. He was beloved by his people, for whose welfare he seems to have honestly labored. Severe and even sanguinary towards individuals, he was just and moderate toward nations. He conquered every enemy, organized a new and better mode of government for his vast dominions, crushed all conspiracies and revolts, and passed the close of his life in peace.