thumb|upright=1.2|Constantine's vision and the Battle of the Milvian Bridge in a 9th-century Byzantine manuscript.

During the reign of the Roman emperor Constantine the Great (306–337 AD), Christianity began to transition to the dominant religion of the Roman Empire. Historians remain uncertain about Constantine's reasons for favoring Christianity, and theologians and historians have often argued about which form of early Christianity he subscribed to. There is no consensus among scholars as to whether he adopted his mother Helena's Christianity in his youth, or, as claimed by Eusebius of Caesarea, encouraged her to convert to the faith he had adopted.

Constantine ruled the Roman Empire as sole emperor for much of his reign. Some scholars allege that his main objective was to gain unanimous approval and submission to his authority from all classes, and therefore he chose Christianity to conduct his political propaganda, believing that it was the most appropriate religion that could fit with the imperial cult. Regardless, under the Constantinian dynasty Christianity expanded throughout the empire, launching the era of the state church of the Roman Empire. Whether Constantine sincerely converted to Christianity or remained loyal to paganism is a matter of debate among historians. His formal conversion in 312 is almost universally acknowledged among historians, despite that it was claimed he was baptized only on his deathbed by the Arian bishop Eusebius of Nicomedia in 337; the real reasons behind it remain unknown and are debated also.

Christians suffered from sporadic and localized persecutions over a period of two and a half centuries. Their refusal to participate in the imperial cult was considered an act of treason and was thus punishable by execution. The most widespread official persecution was carried out by Diocletian beginning in 303. During the Great Persecution, the emperor ordered Christian buildings and the homes of Christians torn down and their sacred books collected and burned. Christians were arrested, tortured, mutilated, burned, starved, and condemned to gladiatorial contests to amuse spectators. The Great Persecution officially ended in April 311, when Galerius, senior emperor of the Tetrarchy, issued an edict of toleration which granted Christians the right to practice their religion, although it did not restore any property to them. Constantine, caesar in the Western Empire, and Licinius, caesar in the East, also were signatories to the edict. It has been speculated that Galerius' reversal of his long-standing policy of Christian persecution has been attributable to one or both of these co-caesars.

Constantine's conversion

It is possible that Constantine's mother, Helena, exposed him to Christianity. In any case, he only declared himself a Christian after issuing the Edict of Milan. Writing to Christians, Constantine made clear that he believed that he owed his successes to the protection of the High God alone.

Vision of Apollo

thumb|[[Jugate gold multiple issued by Constantine at Ticinum in 313, showing the emperor and the god Sol, with Sol also depicted in his quadriga on Constantine's shield.]]

thumb|[[Follis issued by Constantine at Lugdunum , with Sol holding a globe and wearing a radiant crown. Constantine is described as ]]

In 310 a panegyric, preserved in the Panegyrici Latini collection and delivered at Trier for the joint occasion of the city's birthday and Constantine's quinquennalia, recounted a vision apparently seen by the emperor while journeying between Marseille and Trier. The panegyricist recounts that the god Apollo appeared to Constantine in company with Victoria and together presented him with three wreaths representing thirty years of power. bestowed by the hand of God in Christianity on Constantine, "augmenting the sway of his kingdom by long years". According to Eusebius, Constantine also had a dream that same night.

Following the battle and the defeat and death of Maxentius, Constantine became the undisputed emperor in the West and performed an adventus, a ceremonial entrance to the city. The Arch of Constantine, for which numerous reliefs from earlier monuments depicting prior emperors sacrificing to various gods were re-carved with the face of Constantine, does not have an image of Constantine sacrificing to Jupiter, although he is shown sacrificing to Apollo and to Hercules. thereby granting tolerance to all religions, including Christianity. The Edict of Milan went a step further than the earlier Edict of Serdica by Galerius in 311, returning confiscated Church property. This edict made the empire officially neutral with regard to religious worship; it neither made the traditional religions illegal nor made Christianity the state religion, as occurred later with the Edict of Thessalonica of 380. The Edict of Milan did, however, raise the stock of Christianity within the empire and reaffirmed the importance of religious worship to the welfare of the state. Most influential people in the empire, especially high military officials, had not been converted to Christianity and still participated in traditional Roman religion; Constantine's rule exhibited at least a willingness to appease these factions. Coins minted up to eight years after the battle still bore the images of Roman gods.

Patronage of the Church

right|thumb|[[Hagia Eirene was the first church commissioned by Constantine in Constantinople and burned down in the Nika riots. The present structure is 6th century.]]

The accession of Constantine was a turning point for early Christianity. After his victory, Constantine took over the role of patron of the Christian faith. He supported the Church financially, had a number of basilicas built, granted privileges (e.g., exemption from certain taxes) to clergy, promoted Christians to high-ranking offices, returned property confiscated during the Great Persecution of Diocletian, and endowed the church with land and other wealth. Between 324 and 330, Constantine built a new city, New Rome, at Byzantium on the Bosporos, which would be named Constantinople for him. Unlike "old" Rome, the city began to employ overtly Christian architecture, contained churches within the city walls, and had no pre-existing temples from other religions.

thumb|Map of the Church and Empire in the East under Constantine (c. 330 AD).

In doing this, however, Constantine required those who had not converted to Christianity to pay for the new city. This led to the closure of temples because of a lack of support, their wealth flowing to the imperial treasure; Constantine did not need to use force to implement this.

Constantine respected cultivated persons, and his court was composed of older, respected, and honored men. Men from leading Roman families who declined to convert to Christianity were denied positions of power yet still received appointments; even up to the end of his life, two-thirds of his top government were non-Christian. Constantine's laws enforced and reflected his Christian attitudes. Crucifixion was abolished for reasons of Christian piety but was replaced with hanging, to demonstrate the preservation of Roman supremacy. On March 7, 321, Sunday, which was sacred to Christians as the day of Christ's resurrection and to the Roman Sun God Sol Invictus, was declared an official day of rest. On that day markets were banned and public offices were closed, except for the purpose of freeing slaves. There were, however, no restrictions on performing farming work on Sundays, which was the work of the great majority of the population.

Some laws made during his reign were even humane in the modern sense and supported tolerance, possibly inspired by his Christianity: a prisoner was no longer to be kept in total darkness but must be given the outdoors and daylight; a condemned man was allowed to die in the arena, but he could not be branded on his "heavenly beautified" face, since God was supposed to have made man in his image, but only on the feet. Publicly displayed gladiatorial games were ordered to be eliminated in 325.

thumb|4th-century [[sardonyx cameo of Constantine crowned by the Tyche of Constantinople]]

thumb|Gold 1½ [[Solidus (coin)|solidus multiple issued by Constantine at Thessaloniki in 327, with Constantine looking skywards

and an armoured emperor carrying spear and a tropaion with bound captives]]

Early Christian Bibles

According to Eusebius, in 331 Constantine had commissioned him to deliver fifty volumes of scriptures for the churches of Constantinople, which were to be bound in leather and easily portable. Only three or four churches are known certainly to have existed in Constantine's reign, but others appear to have been planned or established, for which the scriptures were commissioned.

Church construction

According to Socrates Scholasticus, Constantine commissioned the construction of the first Church of Hagia Irene in Constantinople, on the site now occupied by the Justinian church of the same name. The Church generally regarded the definition of doctrine as the responsibility of the bishops; the emperor's role was to enforce doctrine, root out heresy, and uphold ecclesiastical unity. The emperor ensured that God was properly worshiped in his empire; what proper worship (orthodoxy) and doctrines and dogma consisted of was for the Church to determine.

Constantine had become a worshiper of the Christian God, but he found that there were many opinions on that worship and indeed on who and what that God was. In 316, Constantine was asked to adjudicate in a North African dispute of the Donatist sect (who began by refusing obedience to any bishops who had yielded in any way to persecution, later regarding all bishops but their own sect as utterly contaminated). More significantly, in 325 he summoned the First Council of Nicaea, effectively the first ecumenical council (unless the Council of Jerusalem is so classified). The Council of Nicaea is the first major attempt by Christians to define orthodoxy for the whole state. Until Nicaea, all previous Church councils had been local or regional synods affecting only portions of the Church.

Nicaea dealt primarily with the Arian controversy. Constantine was torn between the Arian and Trinitarian camps. After the Nicene council, and against its conclusions, he eventually recalled Arius from exile and banished Athanasius of Alexandria to Trier.

Just before his death in May 337, it is claimed that Constantine was baptised into Christianity. Up until this time he had been a catechumen for most of his adult life. He believed that if he waited to get baptized on his death bed he was in less danger of polluting his soul with sin and not getting to heaven. He was baptized by his distant relative Arian Bishop Eusebius of Nicomedia or by Pope Sylvester I which is maintained by the Catholic Church, the Coptic Orthodox Church, the Antiochian Orthodox Church, the Greek Orthodox Church, the Russian Orthodox Church, the Serbian Orthodox Church, upon by many other Eastern Orthodox, Church of the East, and Oriental Orthodox Churches. During Eusebius of Nicomedia's time in the imperial court, the Eastern court and the major positions in the Eastern Church were held by Arians or Arian sympathizers. With the exception of a short period of eclipse, Eusebius enjoyed the complete confidence both of Constantine and Constantius II and was the tutor of Emperor Julian the Apostate. After Constantine's death, his son and successor Constantius II was an Arian, as was Emperor Valens.

thumb|right|Raphael's [[The Baptism of Constantine.]]

According to Hans Pohlsander, professor emeritus of history at the State University of New York at Albany, Constantine's conversion was a matter of realpolitik, meant to serve his political interest in keeping the empire united under his control

Suppression of other religions

Constantine's position on the religions traditionally practiced in Rome evolved during his reign. In fact, his coinage and other official motifs, until 325, had affiliated him with the pagan cult of Sol Invictus. At first, Constantine encouraged the construction of new temples and tolerated traditional sacrifices;

Beyond the limes, east of the Euphrates, the Sasanian rulers, perennially at war with Rome, had usually tolerated Christianity. Constantine is said to have written to Shapur II in 324 and urged him to protect Christians under his rule. With the establishment of Catholicism as the state religion of the Roman Empire, Christians in Persia would be regarded as allies of Persia's ancient enemy. According to an anonymous Christian account, Shapur II wrote to his generals:

Constantinian shift

Constantinian shift is a term used by some theologians and historians of antiquity to describe the political and theological aspects and outcomes of the 4th-century process of Constantine's integration of the imperial government with the Catholic Church that began with the First Council of Nicaea. The term was popularized by the Mennonite theologian John H. Yoder. The claim that there ever was a Constantinian shift has been disputed; Peter Leithart argues that there was a "brief, ambiguous 'Constantinian moment' in the fourth century," but that there was "no permanent, epochal 'Constantinian shift'."

See also

  • Constantinianism
  • Bishops of Rome under Constantine the Great
  • Christian pacifism
  • Labarum
  • List of rulers who converted to Christianity
  • Philip the Arab and Christianity

References

Further reading

  • Eusebius, Life of Constantine, Introduction, translation, and commentary by Averil Cameron and Stuart G. Hall, Oxford: Clarendon Press, 1999.
  • Ramsay MacMullen, Christianizing The Roman Empire A.D. 100–400, Yale University Press, 1984 ,
  • The Full Text of the "Edict of Milan"