A Different Sort of Christian, a Different Sort of Christ:
The Conversion of Constantine The Great
In A.D. 284, the Emperor Numerian died while returning from an expedition in Persia.1 His soldiers declared Diocletian, who had been the commander of the emperor’s bodyguard, emperor. Over time, Diocletian would establish a tetrarchy of emperors to control the empire, with one Augustus ruling in the West and another in the East. Each Augustus would have a Caesar as a junior emperor; Constantius, the father of Constantine, was Caesar under Diocletian’s co-Augustus, Maximian. Through the tetrarchy, Diocletian was able to keep control over the Roman Empire until 305, when he and the other Augustus, Maximian, abdicated in favor of their two Caesars. The tetrarchy did not last long after that date, for civil war soon broke out.
In 303, Diocletian began persecuting the Christians of the empire. In that year, an edict was posted in Nicomedia that ordered all copies of Christian Scriptures to be burned, closed all Christian churches, and forbade Christian gatherings. More edicts followed, ordering all Christians to sacrifice to the pagan gods upon penalty of imprisonment or, in some cases, death. These edicts were sent throughout the empire, but the Caesar Constantius did not fully enforce them in Britain and Gaul. Persecution of Christians was continued by rulers in various parts of the empire until Constantine assumed full power in 324.
In 306, Constantius died in Britain, and Constantine was declared Augustus by his soldiers. Galerius, the senior Augustus, recognized Constantine as Caesar, and he accepted the lesser honor of Caesar. By defeating some competitors and allowing some to remove each other, Constantine would eventually become sole emperor of the entire Roman Empire.
In 312, Constantine invaded Rome in order to take control of the Western Empire by defeating Maxentius, who had taken power in Italy and North Africa. Two other emperors had previously attempted to force Maxentius from power, but both had failed. Eusebius, a historian and Bishop of Caesarea, reports that Constantine saw a vision from God while he marched to Italy with his army. In the vision, a cross of light was set across the sun, with the words, “In this sign conquer” (Latin: in hoc signo vinces). Later, Constantine had a dream in which Christ promised him victory if Constantine would follow Christ. According to Eusebius, Constantine did so before joining battle with the army of Maxentius outside Rome. In the Battle of the Milvian Bridge, Constantine’s army defeated the forces of Maxentius, and during a disorganized retreat Maxentius was drowned and his forces were defeated. Constantine entered Rome as liberator and proclaimed himself the sole emperor of the West. It is at this time that many historians, supported by Eusebius, believe that Constantine may have converted to Christianity. Soon after defeating Maxentius, Constantine issued the Edict of Milan, which granted tolerance for all religions and specifically mentioned Christianity.
While he was Emperor, Constantine attempted to settle major religious disputes that had developed within the Christian Church. Shortly after he defeated Maxentius, he was approached by the Christians of Africa, who asked him to settle a dispute between rival factions of the Donatist schism. Constantine attempted to reconcile the two sides, but he ultimately failed to end the schism. Constantine also attempted to unify the Arians and Catholics by summoning and presiding over the Council of Nicaea in 325, but this also failed to produce a definitive end to the conflict.
In 324, Constantine defeated Licinius, the emperor in the East, and assumed control over the entire Roman Empire. Constantine inaugurated his new capital, Constantinople, in 330, which had been built on the site of Byzantium. Constantine fell ill in 337, and he was baptized in Nicomedia. He would die in that same year.
The Roman Emperor Constantine the Great converted to Christianity after the Battle of the Milvian Bridge, for he believed that he had been granted victory by the Christian God. However, the Christianity to which Constantine converted differed from the Christianity of the day, for despite his overall faith in the power of God his personal religious beliefs retained several pagan elements.
This paper demonstrates that Constantine converted to Christianity, through the examination of the circumstances that surrounded the Battle of the Milvian Bridge, such as Constantine’s motives for attack, his vision and dream, and the effect that his victory had on his religious views. The personal views of Constantine, as they appear in the Edict of Milan and letters issued by Constantine shortly after the Battle of the Milvian Bridge, will also be noted in order to show Constantine’s favorable attitude towards Christians. Finally, this paper will examine the belief system of Constantine in order to explain those actions that seem to conflict with the view that Constantine saw himself as Christian.
Many prominent historians have studied the conversion of Constantine, with varying methods and conclusions. There have been many works on the topic of Constantine’s conversion. Some, like Jacob Burkhardt’s, are important because they demonstrate what not to do. Others, like Michael Grant’s, provide an example on how to best treat the available sources. The works of Norman Baynes and Andreas Alfoldi are primarily important because they introduced new ways of thinking about the conversion.
Jacob Burkhardt wrote an account of the conversion of Constantine in which he portrays the emperor as a cold and calculating politician who used Christianity to unite the Roman Empire under him.2 Burkhardt did not understand Constantine within the context of the time, as he depicts Constantine as a non-religious man.
Norman Baynes’ work on the conversion of Constantine uses the correspondence of Constantine as its primary source of evidence for the conversion; this work is significant because it uses documents that scholars often see as biased and inaccurate, although Baynes states that other scholars have proven the documents’ authenticity.3 Baynes argues that Constantine identified himself with Christianity, not simply philosophical monotheism, and that Constantine also believed that Christianity could unite the Roman Empire. Baynes also addresses the shortcomings of Burkhardt’s work, as Baynes emphasizes placing Constantine within the context of his historical time period.
Andreas Alfoldi argued that Constantine personally converted to Christianity, although he did not immediately act against paganism.4 Alfoldi’s work is important because it emphasizes the power of the Senate, and it argues that political issues would have combined with religious belief to influence Constantine’s policies.
Similarly, Michael Grant argues that Constantine personally converted to Christianity, and, like Baynes, Grant argues that Constantine also used Christianity to further his ultimate goal of uniting the Roman Empire.5 Grant is also important because he evaluates every source, including the coinage of the period; many other works have failed to produce convincing arguments because they did not thoroughly question the sources.
This paper relies in part on several of Constantine’s letters and edicts that were reproduced by Eusebius and Lactantius. True, these historians are not free from biases, but if one wants to understand Constantine and his policies, these sources must be used to some extent.6 In addition, the authenticity of the documents that were reproduced by Eusebius and Lactantius has been attested by several scholars.7 In the end, however, a compromise between dismissal and acceptance must be achieved. Michael Grant uses the letters and edicts attributed to Constantine, but he remains wary of such evidence for several reasons,8 and it is his example that is followed here. The letters and edicts that are attributed to Constantine is used, but used with caution, in this paper.
Other parts of the works by Eusebius and Lactantius, however biased, must also be used, for there is simply not enough available information to dispense with them entirely.9 This is particularly true in their accounts of Constantine’s dream and vision. Lactantius’ account of the dream and vision will not be used, for it reads like a confused summary of Eusebius’ account.10 Thus, in the discussion of the dream and vision Eusebius’ account will be used, and the accuracy of the account itself will be thoroughly discussed as well.
In the matter of numismatic evidence, Grant’s advice also seems to be the most prudent. In his account of the conversion, he used the coins produced by Constantine, but he also exercised caution.11
The Conversion of Constantine
During his invasion of Italy in 312, Constantine was faced with a crisis.12 The tyrant of Rome was protected by the walls of Aurelian, and he was equipped with large supplies of food from his territory in North Africa.13 Both Severus and Galerius had failed in their attack on the city, and it seemed that Constantine would do the same.14 To make matters worse, Constantine was outnumbered, for he had left a large force – perhaps as much as three-fourths of his entire army15 – to guard the frontier.16
Even with these disadvantages, Constantine was convinced that the invasion of Italy was necessary. Despite the strength of his defenses, Maxentius was politically weak in Rome, and any delay would give Maxentius a chance to recover. There was also the chance that, if Constantine did not attack Rome, Licinius would – Maxentius had stationed troops at Verona, perhaps for this very contingency. Constantine had to attack in order to remove Maxentius and take one step closer to his ultimate goal.17
In perspective, Constantine’s actions during his invasion of Italy – such as marching down the Italian peninsula in a direct assault on Rome – might not seem sensible, especially since two attacks on Rome had recently failed. However, these actions were reasonable if Constantine thought that he had some promise of divine aid. This is an argument that Baynes also posits.18
Baynes’ argument, that Constantine acted as though he was confident of divine aid, rests upon an understanding of the people of the third and fourth centuries CE.19 In a search for a parallel character, we need look no further than Maxentius. It seems ironic that in our discussion it is Maxentius, Constantine’s opponent at the Milvian Bridge, who serves as an example of one who had been promised victory from some divine source. As previously stated, Maxentius’ Rome would be able to withstand a considerable siege, and Maxentius himself had planned to wait within the walls of Aurelian. However, when Constantine’s forces arrived, Maxentius rode out from Rome and faced his adversary on the battlefield. The reason for this sudden change was that Maxentius believed he had the aid of the gods. The Sibylline books promised the defeat of the enemy of Rome on that day, and pagan prophets and augurs in Rome predicted the victory of Maxentius. Thus Maxentius believed that he had the aid of the divine, and as a result he abandoned his earlier plan of waiting for a siege.20 The results, of course, were disastrous, but it is important to note the manner in which the usurper acted when he had been assured victory.
For Constantine, this promise of victory came in his famous dream and vision about which Eusebius wrote.21 During the time of Constantine, it was not rare for a person to have visions or dreams and to see them as extremely significant.22 Constantine himself had previously had dreams,23 and he had seen many visions, including one from Apollo.24 Thus it is entirely possible that Constantine had a dream and a vision, or at least that he believed he had.
Still, one must wonder about the validity of the story of the vision. According to Eusebius, the vision was seen by Constantine’s entire army; however, the army was conspicuously silent about the experience.25 Perhaps Constantine simply made up the story in order to legitimize his attack, his victory, or his ultimate rule. But this explanation does not account for Constantine’s decision to march down Italy and confront the numerically superior forces of Maxentius, protected within the Aurelian walls of Rome.
Baynes raises another interesting point, and it is with him that I must ultimately agree. He states that Constantine’s vision occurred, either subjectively or objectively; as historians, we can not definitively know the exact nature of those experiences, but such knowledge would not truly change the discussion at hand.26 Two things are important for this point. First, Constantine related this experience to Eusebius, and he even swore to it.27 In addition, in A.D. 350, the usurper Vetrano attempted to legitimize himself by issuing a coin which depicted himself holding a labarum beneath the words HOC SIGNO VICTOR ERIS, which translates as “by this sign you will be the victor” – a close parallel to the Constantine’s vision.28 Thus, in Constantine’s memory and opinion, the vision did occur. Whether or not it actually happened – the modern reader might be skeptical of such explicit visions – is not specifically important in understanding the result.
After the dream, Constantine questioned the Christians in his court, including Ossius, who interpreted the dream and instructed him about Christ. The precise action that Constantine then took is not clear,29 but this is another instance where the exact nature of the act is not important for this discussion. What is important is that Constantine made some kind of sign in accordance with the dream and vision. This would have been enough of a step to make him believe that he was obeying the divine message and that he would be ensured victory.
We have established that it was possible for Constantine to believe that he had been given a dream and that he had seen a vision. We have also noted that, at a later date, Constantine swore to Eusebius that he had see the vision. Thus the dream and vision truly occurred in the mind of Constantine; this is the promise of divine assistance and victory of which Baynes wrote. Therefore it is no surprise that Constantine, with a relatively small portion of his army, marched down the peninsula of Italy to Rome. Constantine had seen a vision and had a dream that promised him divine aid; we have already seen, in the case of Maxentius, what the effects of such a promise could have.
The circumstances of the Battle of the Milvian Bridge are also important to note, especially the death of Maxentius and the destruction of much of his army during their retreat over the Milvian Bridge.30 During the battle, the armies of Constantine and Maxentius met beside the Tiber. Despite the staunch opposition of the Praetorians, the forces of Maxentius fled in disorder. As they crossed the Tiber on a bridge of boats, the bridge broke, and Maxentius drowned in the Tiber and his army was destroyed.31 It is important to note that Eusebius wrote that Maxentius’ death and the army’s destruction were accomplished by God himself.32 One must wonder if a similar perspective was shared by Constantine. After all, he did march on Rome with the belief that the Christian God would grant him victory, and, although it was Constantine’s army that defeated Maxentius’ in battle, it was the breaking of the bridge that killed Maxentius and won the war. Whether or not Constantine believed that God had performed a conspicuous miracle in order to grant him victory is not particularly important, however – for Constantine had defeated Maxentius. Constantine entered battle knowing that God would eventually give him victory, and he defeated his enemy and took sole control of the West. Thus Constantine first saw the Christian God as a giver of military victory. Constantine’s initial impression of God would not change; most of the depictions on his later coins were militaristic in nature and included the Chi-Rho and the labarum, which he saw as tokens of his victory.33
Thus Constantine entered the Battle of the Milvian Bridge confident that God would grant him victory after he had followed His divine order. Whether or not he saw the breaking of the bridge of boats as a miracle, he was victorious, and this would have a profound effect upon him.
After the Battle of the Milvian Bridge, Constantine acted in a manner consistent with the above conclusions. If one accepts that Constantine entered the battle believing that the Christian God would award him victory, then one must also accept the profound effect that such a victory would have upon him. Baynes uses this point to conclude his argument about the Battle of the Milvian Bridge.34 Alfoldi also mentions this, citing the fact that Constantine was a superstitious man, and because of this the victory would have seriously affected him.35
After the battle, Constantine issued the Edict of Milan, which legalized nearly all religions in the empire. Despite the fact that it did not outlaw paganism, the edict focused on Christians, and it also returned confiscated property to Christians.36 Burkhardt brings up the point that the edict could not have been used as a political instrument for gaining power because of the political weakness of the Christians during the early fourth century. But Burkhardt then refutes this statement by arguing that the edict was used to gather support from the pagans who looked unfavorably upon the persecution.37 However, this argument fails to take into account the amount of emphasis that the edict specifically places on Christianity.38 While this argument falls short of settling the issue, it does raise doubts about the motives behind the edict, and so other documents must be considered.
The actual correspondence of Constantine is important in understanding his personal beliefs.39 Baynes used Constantine’s correspondence for just such a purpose.40 In his letter to Anulinus, Proconsul of Africa, in 313, Constantine followed up his command in the Edict of Milan and ordered that all confiscated property be immediately returned to Christian churches.41 In 313, in a second letter to Anulinus, Constantine exempted Christian clergy from service in all public offices.42 His justification for this exemption is particularly significant. He stated that he was freeing the clergy from public service so that they might focus on the proper worship of the Divinity.43 This Divinity, in return for this proper worship, would then aid the State.44
In a letter to Caecilian, the bishop of Carthage in 313, Constantine alerted the bishop that he has ordered the finance minister of Africa to pay a grant of money to the Church. Constantine also wrote that he would give the Church extra funds if they were needed.45
Thus, shortly after he took sole power of the West by defeating Maxentius, Constantine granted freedom of worship to Christians and others in the Edict of Milan, restored confiscated property to the Church, freed Christian clergy from public service, and bestowed a grant of money to the Catholic Church in Africa. Baynes was correct when he stated of these actions, “this is more than mere tolerance”; at this point, Constantine obviously favored the Christians.46 When this favorable attitude is considered with its timing – so soon after he believed that God had given him victory – one can see that Constantine considered himself to be a follower of the Christian God after the Battle of the Milvian Bridge.
In 337, shortly before his death, Constantine was baptized. The fact that he put off his baptism until he was near death is not especially significant; at the time, many Christians delayed baptism, remaining catechumens for long periods of time, or even most of their lives.47 A.H.M. Jones agrees that his baptism proves that Constantine saw himself as a Christian.48 Barnes also identifies this as no small moment in Constantine’s life as a Christian, as he writes, “now he was truly happy [and he was] illuminated with divine light … Constantine desired to go to God without delay.”49 This may be quite an overstatement, but Barnes’ statement demonstrates his confidence in the thesis that Constantine was a believer in Christ.
In order to establish fully the idea that Constantine actually converted to Christianity, one must also demonstrate that he did not simply nominally choose Christianity for political reasons. Louis Duchesne believes that there is no basis for such an argument, as he states that Constantine had “no political interest in declaring himself a Christian,”50 although this view is opposed by both Grant and Burkhardt.51 One must remember that the Christians were a small minority in the Empire, and that they were still recovering from the persecutions of Diocletian and Galerius.52 In addition, the Roman aristocracy, especially the Senate, was pagan, and it would not look favorably upon an open conversion to Christianity.53 These points also serve to attack Grant’s and Burkhardt’s arguments that Constantine believed Christianity could unite the Empire, for Christians were still a small minority whose belief system was in opposition to that of the established aristocracy. Thus Constantine could gain no direct or immediate political advantages by converting to Christianity.
The evidence that Constantine saw himself as a Christian is simply too much to disregard, including his view of his victory at the Milvian Bridge, his actions immediately following the battle, and his baptism. In addition, it has been shown that, while Constantine believed that God would grant victory to Constantine and benefit the State in return for proper worship, Constantine could not have nominally converted to Christianity for political reasons. Thus Constantine did convert to Christianity; what Constantine actually believed, however, must be dealt with separately.
Constantine’s beliefs were certainly complicated, and must be discussed. As we have seen, Constantine favored the Christian God and saw himself as a Christian. However, after his conversion, his beliefs retained some pagan elements. This is not surprising, for during the time of Constantine the line between paganism and Christianity was blurring, and it would be easy for a pagan to confuse elements of the two. First, paganism was moving towards beliefs that were also held by Christians.54 The pagan religion was becoming monotheistic, at least philosophically, and most educated pagans were also beginning to integrate concepts of morality and redemption into their religion. On the other hand, Christian beliefs could also be confused with those of pagans.55 The Christian Church still recognized the existence of pagan deities, although it saw them as demons. In addition, the rituals of Christianity were similar to those of the mystery religions, especially those of Mithras.56 Finally, the Church often identified Christ with the Sun as an illuminating spirit – specifically, it referred to Christ as the “Sun of Truth.” This could cause people to confuse Christ with such deities as Sol Invictus, “The Unconquered Sun,” who was increasing in popularity among pagans.57 This last point is especially relevant in the discussion of Constantine, for Sol Invictus was the last pagan god to disappear from the imperial coinage.58 Thus it is understandable that Constantine retained elements of paganism after he converted to Christianity.
One pagan idea that Constantine retained was his opinion of theology, particularly that which dealt with the origin of Christ. In a letter to Arius and Alexander, Constantine asked them to forget their theological differences. In Barnes’ words, Constantine “urged Arius and Alexander to act like philosophers.”59 According to Barnes, Constantine also believed that Christians can legitimately agree on certain points while accepting each other in the faith.60 What Constantine did see as important in ensuring the support of God, however, was the actual method of worship.61 This emphasis on ritual rather than theology in religion was an important characteristic of Roman paganism.
Other pagan ideas in which Constantine seems to have believed are the use of divination and magic, which Christians of the day were strongly against. In 321, Constantine outlawed the private use of haruspices (diviners) and magic, although he allowed for the use of haruspices in public ceremonies and spells that were used to heal the sick.62
One point that is particularly troubling to historians is the fact that Constantine continued to subsidize and reward pagans after his supposed conversion. Two examples that Barnes cites are that Constantine subsidized the travel of a priest of the Eleusian mysteries to the tombs of Egypt, and he honored a priest of Apollo because of his devotion to the imperial family. Barnes explains that such actions were taken in order to avoid rebellion or civil disobedience.63 However, while this argument may explain the lack of persecution of pagans, it does not fit well with these examples, for they are active rewards given by Constantine. In order to understand these examples, one can simply accept the fact that in some respects Constantine did not see Christianity as an exclusive religion.
Even if one accepts that Constantine continued to believe in certain pagan elements, one still must also explain why he did not openly proclaim himself to be a Christian after the Battle of the Milvian Bridge. He allowed for a certain amount of ambiguity in the proclamation of his faith; for example, the inscription on the Arch of Constantine reads, instinctu divinitatis, or “by the prompting of the divinity,” and does not name the Christian God specifically.64 Such passive acts on the part of Constantine seem to demonstrate that he saw himself as simply a philosophical monotheist, not as a full Christian. Alfoldi resolved this problem, as he wrote that Constantine omitted explicit references to the Christian God in order to appease the Senate. Due to its prestige and wealth, the Senate could still present a serious opposition against Constantine, who had only recently conquered Italy and needed support.65 According to Alfoldi, Constantine and the Senate of Rome had a certain mutual dependency upon each other.66 The Senate relied on Constantine to free them from Maxentius, who had treated them poorly and who was disliked by the Italian aristocracy.67 Constantine did free them from Maxentius, for when Constantine took power in Rome he was welcomed as the liberator of the city68 and he proceeded to treat the Senate with honor and respect.69 In return for this respect, Constantine required that the Senate recognize him as emperor – Alfoldi clearly states that it was the only body in the Roman Empire that could legitimately do so.70 The Senate also aided Constantine by declaring Maxentius a tyrant and condemning the memory of Maximian.71
Thus Constantine’s policies towards pagans can be explained by two arguments. First, the paganism and Christianity of the time were moving towards one another, and this allowed several pagan elements of religion to remain after Constantine converted to Christianity. Second, Constantine needed to solidify his power in Rome and Italy and to legitimize his claims to the throne after he conquered Rome, and the Senate could do both.
After the Battle of the Milvian Bridge, Constantine saw himself as a Christian. After he received a vision and a dream from the Christian God and followed the divine instructions given, Constantine marched into a battle against a numerically superior foe who had the additional advantage of a nearly unassailable city, with the strong walls of Aurelian and stores of food from North Africa. A victory in such circumstances would warrant his conversion, and Constantine’s victory caused him to truly favor and venerate the Christian God. This is demonstrated by his favorable attitude towards Christians as expressed in several edicts and letters shortly after the battle. The type of Christianity that he practiced and believed, however, retained several elements of paganism. This fact, combined with his dependency on the Roman Senate to legitimize his claims to the throne, explains the policies of Constantine after the battle. Thus Constantine converted to Christianity after the battle, but it was to his own brand of Christianity – one in which God was a giver of victory, and in which many pagan elements still remained.
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Barnes, Timothy D. Constantine and Eusebius. Cambridge, MA: Harvard University
Baynes, Norman. Constantine the Great and the Christian Church. London: H. Milford,
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Burkhardt, Jacob. The Age of Constantine the Great. trans. by Moses Hadas. Los
Angeles: University of California Press, 1949.
Duchesne, Louis. Early History of the Christian Church. Vol. II. New York:
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Eusebius. The History of the Church. Book IX.
Gibbon, Edward. The Decline and Fall of the Roman Empire. Chapters XIV-XVI; XX-
XI. New York: Viking, 1952.
Grant, Michael. Constantine the Great: The Man and His Time. New York: Scribner’s,
Jones, A.H.M. Constantine and the Conversion of Europe. Toronto: University of
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Stevenson, J., ed. A New Eusebius. rev. ed. Cambridge: University Press, 1987.