The Christians of the Eastern Empire maintained the primitive religion, and persevered in their original opposition to bearing arms in war, and to slavery, and to private-property rights, and so added nothing to the military power of Licinius, except their constantly increasing communal wealth. Licinius simply left the Church at peace, and was not consummate politician enough to use its vast resources in aid of his government, as Constantine had done, by inducing the Christians to abandon the primitive organization of the Church and become Roman subjects in everything except the mere article of faith. When Ulfilas, the Goth, converted his barbarous countrymen, and transformed the fierce and warlike tribes into peaceful and settled peoples among whom war, slavery, polygamy, and private property, were unknown, and among whom no king was recognized but Christ, Constantine declared war against them, and pursued them with fire and sword until they were forced to adopt Roman laws and customs, and agreed by treaty to supply a permanent force of forty thousand young men to the imperial army; and, after that, he caused Ulfilas himself to be ordained a bishop, and sent him back to his own people to teach the imperial religion instead of Christianity. But this profound and atheistic policy was too deep for the Emperor Licinius; and Constantine knew well that, according to the primitive Christianity, a whole Christian province would not furnish a single recruit to his rival's legions, since no Christian would bear arms.
Eusebius of Cæsarea, who had prepared the way for Constantine to become the head of the Church in the Western Empire, was the emperor's chosen friend and constant counselor, and the ruler of Rome never forgot that the bishop had, first of all men, invited his attention to the fact that the despised and persecuted Christians constituted already a body of men so numerous, so virtuous, and so prosperous, as to hold the balance of power between any factions which might divide the Roman people just as soon as the legal disabilities which both concealed their numbers and fettered their influence might be removed by imperial favor.
Under the advice of Eusebius, the emperor, in his own name, sent to Anulinus, Proconsul of Africa, a decree most favorable to the Christians throughout that region; he also made presents of large sums of money to the bishops of Africa, Numidia, and Mauritania, who had been plundered in the persecutions of Maximian; he also sent a decree ordaining that all church prelates be freed from obligation to discharge any public, military, or political duties and offices; also, he made a decree commanding a certain council to be held concerning the affairs of Cæcilianus, Bishop of Carthage, and sent to Miltiades, Bishop of Rome, copies of the charges against Cæcilianus; also, a decree addressed to Chrestus, Bishop of Syracuse, commanding that a council of many bishops, both of Africa and of Gaul, should assemble at the city of Arles, in order to consider and determine certain questions which were disputed among the faithful.
In short, counseled by Eusebius, who never doubted the ultimate overthrow of idolatry, and the ultimate triumph of whatever ecclesiastical system might be established in place of the Christian communities, Constantine zealously strove in every way to identify himself and his government with the new religion, and to hold himself out as the head of the Church, as well as of the state. At the same time he steadily pursued a secret policy of winning to himself the affection and confidence of the Christian subjects of the Emperor Licinius, by the use of agents whom he kept in his own service, in the household of every bishop of the Eastern Church. This zeal in the service of the established ecclesiasticism soon met with the great reward which Eusebius had promised to the emperor; for, throughout the length and breadth of the churches it began to be commonly declared that "Constantine was the divinely-appointed protector of the Christians"; that "God was the friend and vigilant protector of Constantine"; and that "no man could be his equal, and no man could stand against him." Licinius soon perceived the influence of these machinations, and saw that, even in his own dominions, the Christians, and especially the prelates, offered up more prayers for Constantine than for himself--"so that he did not suppose," saith Eusebius, "that they offered prayers for him at all, but persuaded himself that they did all things, and propitiated the Deity, only for the divinely-favored Emperor Constantine."
This treasonable sentiment, of course, aroused the resentment of the jealous Licinius, and more and more developed that estrangement between him and the Christians for which Constantine secretly but zealously labored; and Licinius sought revenge by fomenting every disaffection which manifested itself against the rule of Constantine in Africa. But the bishops were as perfect a police force as modern times have ever succeeded in organizing, and kept Rome fully advised of every movement inaugurated by the enemies of the "most Christian emperor." And Eusebius saith, concerning Licinius, that "when he saw that his secret preparations by no means succeeded according to his wish, as God detected every artifice and villainy to his favorite prince, no longer able to conceal himself, Licinius commenced an open war. And in thus determining war against Constantine, he now proceeded to array himself against the Supreme God whom he knew Constantine to worship. Afterward he began imperceptibly to assail those pious subjects under him who had never at any time troubled his government. This too, he did, violently urged on by the innate propensity of his malice, that overclouded and darkened his understanding. He did not, therefore, bear in mind those that had persecuted the Christians before him, nor those whose destroyer and punisher he himself had been appointed, for their wickedness. But, departing from sound reason, and, as one might say, seized with insanity, he had determined to wage war against God himself, the protector and aid of Constantine, in place of the one whom He assisted. And first, indeed, he drove away all the Christians from his house, the wretch thus divesting himself of those prayers to God for his safety which they were taught to offer up for all men. After this he ordered the soldiers in the cities to be cashiered and stripped of military honors unless they chose to sacrifice to demons."
Constantine having craftily succeeded in embroiling Licinius with the Church, watched with secret joy, until the enemy whom he wished to destroy followed up this lustration of his army and navy, which was designed to drive out the Christian spies of Constantine, with more strenuous measures; and, in the language of Eusebius, "at last proceeded to such an extent of madness as to attack the bishops, now indeed regarding them as the servants of the Supreme God, but hostile to his measures." And as the angry tyrant adopted extreme remedies for this ecclesiastical treason, "razing the churches to the ground"; "subjecting the bishops to the same punishment as the worst criminals"; "cutting the bodies of some into small pieces and feeding them out to fishes in the sea"; and "destroying others by various modes of torture and death"--"the whole Christian world regarded him with horror and detestation, and looked to Constantine for deliverance."
So that the error which the emperor had committed, in soliciting Licinius to affix his signature to the Decree of Milan, was not only fully compensated by his consummate skill and artifice, but the Church prayed earth and Heaven for the destruction of Licinius. Licinius, irritated more and more by the wide-spread disaffection of his subjects, espoused the cause of Bassianus, who had married Anastasia, the sister of Constantine, and urged him into rebellion in order to gain larger power; and, Bassianus having been defeated and dethroned, Licinius refused to deliver up the partisans of the fallen Cæsar who had taken refuge in his dominions; and upon this pretext Constantine declared war against him; and in two battles, one at Cibalis in Pannonia, and the other upon the plains of Mardia in Thrace, he defeated Licinius, and so crippled him that he was compelled to make peace, with the loss of Pannonia, Dalmatia, Dacia, Macedonia, and Greece, which provinces were added to the dominions of Constantine, and extended his empire to the extremity of Peloponnesus, leaving Licinius Emperor of Thrace, Asia Minor, Syria, and Egypt.
This war happened in the year 315, and the ambition of Constantine was temporarily sated, so that he then refrained from pushing to extremities the defeated but still powerful Licinius until he might have time and opportunity to alienate the affection and confidence of his subjects in Asia as thoroughly as he had done in Europe. And, besides this, he wanted time in order to subjugate the Goths whom Ulfilas had converted, subvert the Christian communities organized among them on the primitive foundation, and force them to adopt the ecclesiastical system which he had established at Rome, in order to make the Gothic nation an available factor in any future war in which he might engage. But in a few years afterward, having successfully waged war against the Goths, and having seen the influence of Licinius greatly impaired by the persecutions of the Church in Syria and Egypt which he had encouraged and, perhaps, instigated, as well as by that secret diplomacy of which Constantine was master, the Roman emperor deemed that the time had come to destroy Licinius, and restore the unity of the empire, and consolidate all power in his own hands, especially as the great age and unpopular vices of Licinius seemed to presage an easy victory. He accordingly (and without any pretext whatever on this occasion) declared war against the Illyrian emperor; and in the great battle of Adrianople, and in the siege of Byzantium, and in the decisive action of Chrysopolis, in all of which he engaged Licinius with inferior numbers, his vast military genius asserted itself, so that by continuous defeats he reduced the Emperor of the East to the necessity of making an unconditional surrender. Constantia, the wife of Licinius, was the sister of Constantine, and, at her request and entreaties, the conqueror temporarily spared the life of his fallen rival, and banished him to Thessalonica, where he was soon afterward assassinated in some mysterious manner, it being to this day uncertain whether he perished by the order of the senate, by a tumult of the soldiers, or by the machinations of Constantine. But it is certain that the "first Christian emperor" regarded the fact that a man might stand in the way of his ambition, or possibly compromise his safety, as a sufficient reason for putting him to death, even if the unlucky person happened to be his own son.
"Thus the mighty and victorious Constantine," saith Eusebius, "adorned with every virtue of religion, with his most pious son, Crispus Cæsar, resembling in all things his father, recovered the East as his own, and thus restored the Roman Empire to its ancient state of one united body; extending their peaceful sway around the world, from the rising sun to the opposite regions, to the north and the south, even to the borders of the declining day."
But this greatest statesman, politician, and ruler--this absolute, untroubled, and self-confident atheist--had only "the godliness that is profitable for the life that now is"; for this "Christian" had never been baptized (knowing that an emperor can not be a Christian); and he afterward murdered in cold blood, without provocation, "his most pious son, Crispus Cæsar, resembling in all things his father"; his own wife Fausta, and the youthful Licinius, son of his sister Constantia; just as he systematically assassinated every one whom his calm, merciless, wise policy thought to be possibly inimical to his own safety. But he realized the life-long ambition of his soul, the restoration of the unity of the Roman Empire under his own authority; and did it by the aid of the Christian Church, which he bribed, corrupted, and secularized, until it acknowledged him to be king instead of Jesus Christ.