By a decree issued from Milan A.D. 313, Christianity was made in effect the state religion; but all other forms of worship were tolerated. With the view of harmonizing the different sects that had sprung up among the Christians, and to settle the controversy between the Arians and the Athanasians respecting the nature of Christ,—the former denied his equality with God the Father,—Constantine called the first OEcumenical, or General Council of the Church, at Nicæa, a town of Asia Minor, A.D. 325. Arianism was denounced, and a formula of Christian faith adopted, which is known as the Nicene Creed.

After the recognition of Christianity, the most important act of Constantine was the selection of Byzantium, on the Bosporus, as the new capital of the empire. One reason which led the emperor to choose this site in preference to Rome was the ungracious conduct towards him of the inhabitants of the latter city, because he had abandoned the worship of the old national deities. But there were political reasons for such a change. Through the Eastern conquests of Rome, the centre of the population, wealth, and culture of the empire had shifted eastward. The West—Gaul, Britain, Spain—was rude and barbarous; the East—Egypt, Syria, Asia Minor—was the abode of ancient civilizations from which Rome was proud to trace her origin. Constantine was not the first to entertain the idea of seeking in the East a new centre for the Roman world. The Italians were inflamed against the first Cæsar by the report that he intended to restore Ilium, the cradle of the Roman race, and make that the capital of the empire.

Constantine organized at Byzantium a new Senate, while that at Rome sank to the obscure position of the council of a provincial municipality. Multitudes eagerly thronged to the new capital, and almost in a night the little colony grew into an imperial city. In honor of the emperor its name was changed to Constantinople, the "City of Constantine." Hereafter the eyes of the world were directed towards the Bosporus instead of the Tiber.

To aid in the administration of the government, Constantine laid out the empire into four great divisions, called prefectures (see map), which were subdivided into thirteen dioceses, and these again into one hundred and sixteen provinces.

The character of Constantine has been greatly eulogized by Christian writers, while pagan historians very naturally painted it in dark colors. It is probable that he embraced Christianity, not entirely from conviction, but partly from political motives. As the historian Hodgkin puts it, "He was half convinced of the truth of Christianity, and wholly convinced of the policy of embracing it." In any event, Constantine's religion was a strange mixture of the old and the new faith: on his medals the Christian cross is held by the pagan deity, Victory. In his domestic relations he was tyrannical and cruel. He died in the thirty-first year of his reign, leaving his kingdom to his three sons, Constans, Constantius, and Constantine.

REIGN OF JULIAN THE APOSTATE (A.D. 361-363).—The parcelling out of the empire by Constantine among his sons led to strife and wars, which, at the end of sixteen years, left Constantius master of the whole. He reigned as sole emperor for about eight years, engaged in ceaseless warfare with German tribes in the West and with the Persians [Footnote: The great Parthian empire, which had been such a formidable antagonist of Rome, was, after an existence of five centuries, overthrown (A.D. 226) by a revolt of the Persians, and the New Persian, or Sassanian monarchy established. This empire lasted till the country was overrun by the Saracens in the seventh century A.D.] in the East. Constantius was followed by his cousin Julian, who was killed while in pursuit of the troops of Sapor, king of the Persians (A.D. 363).

Julian is called the Apostate because he abandoned Christianity and labored to restore the pagan faith. In his persecution of the Christians, however, he could not resort to the old means—"the sword, the fire, the lions;" for, under the softening influences of the very faith he sought to extirpate, the Roman world had already learned a gentleness and humanity that rendered impossible the renewal of the Neronian and Diocletian persecutions. Julian's weapons were sophistry and ridicule, in the use of which he was a master. To degrade the Christians, and place them at a disadvantage in controversy, he excluded them from the schools of logic and rhetoric.

Furthermore, to cast discredit upon the predictions of the Scriptures, Julian determined to rebuild the Temple at Jerusalem, which the Christians contended could not be restored because of the prophecies against it. He actually began excavations, but his workmen were driven in great panic from the spot by terrific explosions and bursts of flame. The Christians regarded the occurrence as miraculous; and Julian himself, it is certain, was so dismayed by it that he desisted from the undertaking. [Footnote: The explosions which so terrified the workmen of Julian are supposed to have been caused by accumulations of gases—similar to those that so frequently occasion accidents in mines—in the subterranean chambers of the Temple foundations.]

It was in vain that the apostate emperor labored to uproot the new faith; for the purity of its teachings, the universal and eternal character of its moral precepts, had given it a name to live. Equally in vain were his efforts to restore the worship of the old Grecian and Roman divinities. Polytheism was a transitional form of religious belief which the world had now outgrown: Great Pan was dead.

The disabilities under which Julian had placed the Christians were removed by his successor Jovian (A.D. 363-4), and the Christian worship was re- established.