Contrary to popular imagery, hunting Christians was not the first priority of the Roman Empire. Only under the specific direction of reigning emperors and at times of particular crisis (which were put down to the Christians not worshipping the state gods) were persecutions enforced:

Nero.
Trajan (98-117) wrote the famous response to Pliny the Younger's letter regarding how Christians should be treated. Also, Ignatius of Antioch was martyred in his reign.
Septimius Severus (193-211) ordered provincial governors to round up Christians and punish them according to the local governor's preference.
Decius launched the first Empire wide persecution against Christians in 250, but military concerns soon led to a loss of interest and the persecution was stopped.
Valerian had led Decius' persecution and in 257 he re-enacted the original edict and in 258 added more stringent measures that targeted clergy with summary execution.
The Great Persecution 303-311 of Diocletian (284-305) was the most extreme; he ordered Christian buildings (and the homes of Christians) torn down, their sacred books collected and burned, and Christians themselves were denied the protection offered other citizens by Roman law. Christians were arrested, tortured, mutilated, burned, starved, and forced to gladiatorial contests to amuse spectators. His successor Galerius (305-311) was responsible for the more draconian aspects of this persecution, and some argue that it was he who persuaded Diocletian to launch the persecution after the success of the persecution against the Manichees, a religion based in Persia, then a resurgent threat to the Empire's Eastern border.
Most of the time Christianity was tolerated, though not officially allowed. Alexander Severus was even friendly to the Christian movement and built a shrine to Jesus in his own home next to his shrines to the Roman gods. [citation needed] After emperor Valerian was captured by the Persians in 260, his son and successor Gallienus abandoned the persecution of Christians. Until the start of the Great Persecution, Christianity enjoyed over 40 years of relative peace without major persecutions.

The Great Persecution officially ended in 311, when Galerius, then senior emperor of the Tetrarchy, issued an edict of toleration, which granted Christians the right to practice their religion, though it did not restore any property to them.


[edit] Constantine's conversion

Constantine's conversion, by Rubens.
[edit] Sincerity
Constantine is best known for being the first Roman Emperor to embrace Christianity, although he may have continued in his pre-Christian beliefs as well. Fifth Century historian Salminius Hermias Sozomen wrote that Constantine was converted to Christianity in Gaul and Britain saying:

, that it was then no easy matter to dwell in Gaul, in Britain, or in the neighboring countries, in which it is universally admitted Constantine embraced the religion of the Christians,, [1]
Some modern scholars, however, question the historicity of his conversion. [citation needed] This includes those who refer to the Church tradition that he was not baptised until his deathbed, and it was only witnessed by the same Christian leaders that made the subsequent claims of his baptism. That delay is likely to be linked to a then widely held belief that only pre-baptismal sins could be forgiven, so many postponed baptism as long as they could. [citation needed]

Constantine even turned to preaching in later life, giving his own sermons in the palace before his court and invited crowds, preaching harmony at first, but gradually turning more confrontational with the old pagan ways. The reason for this later "change of heart" remains conjectural.

Many historians, including philospher Bertrand Russell, believe Constantine favored Christianity due to its organization and contagious zeal:

“In the modern world, we are accustomed to political organization; every politician has to reckon with the Catholic vote, but it is balanced by the vote of other organized groups. A Catholic candidate for the Presidency is at a disadvantage, because of Protestant prejudice. But, if there were no such thing as Protestant prejudice, a Catholic candidate would stand a better chance than any other. This seems to have been Constantine's calculation. The support of the Christians, as a single organized bloc, was to be obtained by favouring them. Whatever dislike of the Christians existed was unorganized and politically ineffective. Probably Rostovtseff is right in holding that a large part of the army was Christian, and that this was what most influenced Constantine. However that may be, the Christians, while still a minority, had a kind of organization which was then new, though now common, and which gave them all the political influence of a pressure group to which no other pressure groups are opposed. This was the natural consequence of their virtual monopoly of zeal, and their zeal was an inheritance from the Jews." Bertrand Russell, a History of Western Philosophy
Peter Novak also alludes in his book Original Christianity that Constantine utilized Christianity to strike fear and condemn souls to eternal damnation:

"With a renewed alignment of church and state, the people would no longer merely fear the ability of the state to take their lives, but would then also fear its ability to condemn their souls to eternal damnation in the afterlife. A government that could get the population to believe it had such power would possess the most successful populace control system imaginable." Peter Novak, Original Christianity

[edit] Constantine's vision
The traditional story of Constantine's conversion is presented as Constantine seeing an omen in the sky whilst marching along with his troops — in front of the sun, the shape of an ambigram cross with two Greek letters, chi (Χ) and rho (Ρ) (the first two letters of the Greek ΧΡΙΣΤΟΣ, Christos, or Christ) along with a Greek inscription reading "Εν τούτω Νίκα", En Touto Nika (meaning "with(in) this you win", which is often translated into the more familiar Latin: In hoc signo vinces (meaning "in this sign thou shalt conquer" before his victory in the Battle of Milvian Bridge on October 28, 312.

Either upon seeing this vision or upon being instructed to use the emblem he had just seen as a standard in a dream afterwards [citation needed], Constantine is said to have instituted a new standard to be carried into battle, the labarum. Another major religion of the time, Sol Invictus, also used a similar symbol. [citation needed]

There are at least three different surviving ancient versions of this battle in greater detail, not all of them are by prominent Christian apologists:

Panegyric of Constantine, sees the vision as from Apollo as Constantine's patron (Panegyrici Latini VI (7), 21 from 310);
Lactantius, Of the manner in which the persecutors died, 44;
Eusebius of Caesarea, The life of Constantine, 24-31;
Zosimus, New History, 2 (43,44) (this version seems to have numerous owls as an omen of victory, and is by a hostile pagan).
It should be noted that historical sources of the 4th century Roman Empire seem to be unusually rich in omens, magic, hexes and spells, while lacking in critical inquiry.[2] A suspicion of literacy and higher learning which began at least a century before had grown. These may have been the results of the fear and high mortality rates caused by the first and second outbreak of the Antonine Plague (165 - 180 and 251 - 266 respectively).


[edit] Other influences
Family influence is also thought to account for Constantine's alleged later, death-bed adoption of Christianity: Helena is said to be "probably born a Christian" though virtually nothing is known of her background, save that her mother was the daughter of an innkeeper and her father a successful soldier, a career that excluded overt Christians. Helena became known later in life for numerous pilgrimages.

The sign in the sky was not in Latin but Greek: En touto Nika (in this, victory). Also, Constantine was responsible for declaring Sunday to be a day of rest for the empire, though early Christians had already been celebrating on Sunday (as opposed to on Saturday, the day of the Jewish Sabbath) since the first century because it was the day of the Resurrection. Sunday was the day which the Roman state had dedicated to Sol Invictus (following the Egyptian tradition of associating that day with the worship of the sun), the main rival religion to Christianity at the time, and of which Constantine was chief priest (pontifex maximus) until his death.


[edit] Constantine's edicts and actions

Coin of Constantine I, making a benediction gesture, with his sons, enthroned.Along with his co-Emperor Licinius, Constantine was the first to grant Christianity the status of an allowed religion (religio licta). Their so-called Edict of Milan of 313 removed penalties for professing Christianity , under which many had been martyred in previous persecutions of Christians (ie legalized it), and returned confiscated Church property. However, it neither made paganism illegal nor made Christianity a state-sponsored religion, but instead granted religious freedom.

There is no historical evidence that an Edict of Milan was ever issued as a formal legal document[3]. Licinius after returning to his Eastern portion of the Empire, issued a decree from Constantine and himself, but we have no surviving writing from Constantine on this topic. What is claimed as the text of the edict [2] is not a joint "Edict of Milan," but something issued by Licinius in the East.


[edit] Public office
After the Edict, new avenues were opened to Christians, including the right to compete with pagan Romans in the traditional cursus honorum for high government positions, and greater acceptance into general civil society.

Constantine respected cultivation, and his court was composed of older, respected, and honored men. Leading Roman families that refused Christianity were denied positions of power, yet pagans still received appointments, even up to the end of his life, and two-thirds of his top government was non-Christian.[4]


[edit] Army
Considered a critical component of Roman society, the army was a prime target for conversion. Exerting his absolute power, Constantine had the army recite his composed Latin prayer in an attempt to convert them to Christianity, which failed. It was unpopular in the army both because it accepted women, and because the soldiers generally were members of other religions such as those of Mithras and Isis. [citation needed]


[edit] Church building
He began a large building program of churches in the Holy Land, which while greatly expanding the faith also allowed considerable increase in the power and wealth of the clergy. New churches were allowed to be built, often under Constantine's (or his mother Helena's) patronage, under which the church prospered. He gave the Lateran Palace to the Pope, ordered the building of:

in the Holy Land:
the Church of the Nativity in Bethlehem
Church of the Holy Sepulchre in Jerusalem
in Rome:
Saint Peter's Basilica
an oratory now the Basilica di San Lorenzo fuori le Mura
Basilica of Saint Paul Outside the Walls
in Constantinople
Hagia Sophia
the Church of the Holy Apostles where he was entombed.

[edit] Clergy
The clergy were patronised by Constantine, and received legal perks. Christian leadership became increasingly bold — Christian bishops became prominent and took aggressive public stances that were unheard of among other religions, drawing a hostile pagan reaction and the outlawing of public Proselytism. [citation needed]


[edit] Internal church controversy
Christianity's new status meant that church controversies, lively within the Christian communities since the mid-2nd century, now flared (often with violent acts) into public schisms — see, for example, the Donatist schism in Africa. Constantine, believing himself divinely appointed, saw quelling religious disorder as the divinely-appointed emperor's duty. [citation needed] He therefore called the 314 Council of Arles against the Donatists and, after becoming Emperor of the East, the first Ecumenical Council: the First Council of Nicaea (May 20 - July 25, 325), to settle some of the doctrinal problems plaguing early Christianity, notably Arianism and Quartodecimanism.


[edit] Legal reforms
Constantine's laws enforced and reflected his Christian reforms:

Crucifixion was abolished for reasons of Christian piety, but was replaced with hanging, to show there was Roman law and justice.
Easter could be publicly celebrated.
On March 7, 321, Sunday was declared the official day of rest, on which markets were banned and public offices were closed (CJ 3.12.2). (except for the purpose of freeing slaves). However, there were no restrictions on farming work (which was the work of the great majority of the population).[5]
Some were even humane in the modern sense, possibly originating in 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, just on the feet (because God made man in His image).
Gladiatorial games were ordered to be eliminated in 325, although this had little real effect.
A slave master's rights were limited, but a slave could still be beaten to death.

[edit] Opposing paganism?
Neither the Edict nor later Constantinian legislation outlawed paganism. However, :"From Pagan temples Constantine had his statue removed. The repair of Pagan temples that had decayed was forbidden. These funds were given to the favored Christian clergy. Offensive forms of worship, either Christian or Pagan, were suppressed. At the dedication of Constantinople in 330 a ceremony half Pagan and half Christian was performed, in the market place, the Cross of Christ was placed over the head of the Sun-God's chariot [with], a singing of hymns."[6]

Pagans were also still wary of Christians for their public refusal to "sacrifice and build idols" (which some modern writers see as an oath of allegiance). Consistent with the Roman idea that they ruled by the favor of the gods, refusal to build idols was seen as something that might easily bring upon all the Roman people the loss of the divine favor and protection. In hoc signo vinco was an attempt to show that this new god also gave Rome divine protection.

Also, as Christianity began to move from a position of toleration to one of preference after Constantine, followers of the old religion turned to appeals to the state to protect their own traditions. For example, in 340, when the Altar of Victory was desecrated and removed from its place of honor in the Senate, the Senate deputized Quintus Aurelius Symmachus, prefect of Rome, to appeal to the Emperor for its return. In his plea for freedom of religion, Symmachus publicly characterized the late Emperor Constantine's policy thus:

"[Constantine] diminished none of the privileges of the sacred virgins, he filled the priestly offices with nobles, he did not refuse the cost of the Roman ceremonies, and following the rejoicing Senate through all the streets of the eternal city, he contentedly beheld the shrines with unmoved countenance, he read the names of the gods inscribed on the pediments, he enquired about the origin of the temples, and expressed admiration for their builders. Although he himself followed another religion, he maintained its own for the empire, for everyone has his own customs, everyone his own rites. The divine mind has distributed different guardians and different cults to different cities. As souls are separately given to infants as they are born, so to peoples the genius of their destiny." (Possible Christian insertion in italics.)
—Medieval sourcebook: "The Memorial of Symmachus, prefect of the City". (The Memorial has been emended to address three emperors, Valentinian II (died 392), Theodosius I, and Arcadius. Arcadius was named co-ruler of his father and Augustus in January, 383. So the address to the three Augusti could have been written anywhere between 383 and 392. There may be Christian adulterations of the text. The reply of Ambrose, Bishop of Milan, is appended, which is highly revealing in the character of his argument in rebuttal.)[7]

[edit] Constantine and the Jews
See also: Christianity and anti-Semitism#The Emperor Constantine the Great
Constantine instituted several legislative measures regarding the Jews: they were forbidden to own Christian slaves or to circumcise their slaves. Conversion of Christians to Judaism was outlawed. Congregations for religious services were restricted, but Jews were allowed to enter Jerusalem on Tisha B'Av, the anniversary of the destruction of the Temple. Constantine also supported the separation of the date of Easter from the Jewish Passover (see also Quartodecimanism), stating in his letter after the First Council of Nicaea: ", it appeared an unworthy thing that in the celebration of this most holy feast we should follow the practice of the Jews, who have impiously defiled their hands with enormous sin, and are, therefore, deservedly afflicted with blindness of soul. , Let us then have nothing in common with the detestable Jewish crowd; for we have received from our Saviour a different way." [8]. Theodoret's Ecclesiastical History 1.9 records the Epistle of the Emperor Constantine addressed to those Bishops who were not present at the Council: "It was, in the first place, declared improper to follow the custom of the Jews in the celebration of this holy festival, because, their hands having been stained with crime, the minds of these wretched men are necessarily blinded. , Let us, then, have nothing in common with the Jews, who are our adversaries. , avoiding all contact with that evil way. , who, after having compassed the death of the Lord, being out of their minds, are guided not by sound reason, but by an unrestrained passion, wherever their innate madness carries them. , a people so utterly depraved. , Therefore, this irregularity must be corrected, in order that we may no more have any thing in common with those parricides and the murderers of our Lord. , no single point in common with the perjury of the Jews." [9]


[edit] Reactions and reflection

[edit] Persian reaction
Beyond the limes, east of the Euphrates, the Sassanid rulers of the Persian Empire had usually tolerated their Christians. A letter supposedly from Constantine to Shapur II (both lived and reigned from 310 to 379), written in c. 324 urged him to protect the Christians in his realm. With the edicts of toleration in the Roman Empire, Christians in Persia would now be regarded as allies of Persia's ancient enemy, and were thus persecuted. Shapur II wrote to his generals:

You will arrest Simon, chief of the Christians. You will keep him until he signs this document and consents to collect for us a double tax and double tribute from the Christians … for we Gods have all the trials of war and they have nothing but repose and pleasure. They inhabit our territory and agree with Caesar, our enemy. (quoted in Freya Stark, Rome on the Euphrates 1967, p. 375)
The Sassanids were perennially at war with Rome, (which incidentally raises further doubt on the authenticity of this letter). Christians were now suspected for potential treachery. The "Great Persecution" of the Persian Christian churches occurred in a later period, 340 to 363, after the Persian Wars that reopened upon Constantine's death. In 344 came the martyrdom of Catholicos Shimun bar Sabbae, with five bishops and 100 priests.


[edit] Historical reflections on Constantine's actions
Christian historians ever since Lactantius have adhered to the view that Constantine "adopted" Christianity as a kind of replacement for the official Roman paganism. Though the document called the "Donation of Constantine" was proved a forgery (though not until the 15th century, when the stories of Constantine's conversion were long-established "facts" it was attributed as documenting the conversion of the Roman Empire to Christianity for centuries. Even Christian skeptics have accepted this formulation, though seeing Constantine's policy as a political one, unifying and strengthening the Empire, rather than a spiritual move. Still the Edict of Milan indicated that reverence to the divine, as shown by past events, was for the good of the Roman Empire.

Despite the questions surrounding Constantine, he is celebrated as a major Saint of Eastern Orthodoxy, together with his mother Helena (both feasted on 21 May). The emperor is not only considered an example of a "Christian monarch" (isapostolos - "equal to the Apostles", he is associated, albeit in retrospect, with the idea of a "Second Rome" - the Byzantine one.

Genuine knowledge seekers ought to read this article.

Interesting. I'm actually taking a course on this stuff starting next week. I was going to start a thread on it when classes start but I guess I can just do it here instead. This is the course outline for anyone interested, and I`ll be updating with lots of info 2ce a week. Kunleoshob, lookin forward to your contribution. . 

RS 231R -  A HISTORY OF CHRISTIAN THOUGHT

Renison Rm. 2102 Professor: M. Darrol Bryant
Tues. & Thurs. 2:30 – 3:50 p. m.

An overview of the leading developments in the history of Christian thought from the first to the twentieth century. Emphasis will be on the major theological developments, movements and representative figures that contribute to Christian self-understanding. Christian thought will be examined in its varying cultural and ecclesial settings.

Course OUTLINE
I. PRELIMINARY DEFINITIONS: The Scope of the Course
II. BACKGROUNDS: Religious, Intellectual and Social
A. The Hebrew Heritage, B. The Greek Milieu, C. The Roman Empire
D. Christian Thinking in the Bible: Paul and the Synoptics
III. SETTING FOUNDATIONS: The Challenges of the First Generations
A. Martyrdom and Persecution B. Canon and Community
C. Scripture and Tradition D. Church Order and Christian Life
E. Apostolic Fathers: Ignatius and Clement
F. Christian Apologist: Justin Martyr and Tertullian
IV. ARTICULATING THE FAITH: Christianity in the Ancient World
A. The Challenge of Marcion B. Irenaeus: The Struggle for Orthodoxy and Creedal Theology C. The Alexandrian Way: Biblical Faith and Greek Thought D. Origen: The Beginnings of Systematic Theology
V. TOWARDS DOGMATIC DEFINITION: The Route to the Councils
A. Towards Christological Definition B. Athanasius and Arius
C. Nicea (325) to Chalcedon (451) D. Towards Trinitarian Definition
E. The Cappadocian Fathers
VI. AUGUSTINE: Architect of Western Christian Thought
A. Confessions B The City of God C. On the Trinity D. Pelagianism, Donatism and all that . . . E. The Orthodox Critique
VII. THE RISE OF MONASTICISM AND SCHOLASTICISM
A. Benedict: Architect of Western Monasticism B. Anselm: Faith Seeking Understanding C. Reason and Revelation: The Great Debate D. Lombard to Abelard: The Search for a Method E. The Grammar of Christian Spirituality
VIII. THE SCHOOLMEN And THE RETURN OF ARISTOTLE
A. The Angelic Doctor, B. The Medieval Synthesis
C. The Harvest and End of Medieval Scholasticism
IX. THE REFORMATION: The Emergence of Protestant Traditions
A. Luther: The Centrality of Justification B. Calvin: The Centrality of the Glory of God C. Simons: The Centrality of Christian Community D. The Anglican Way: Hooker and the "Laws of Ecclesiastical Polity" E. Reform in the Catholic World: Erasmus, Theresa of Avila, and Ignatius.
X. REFORMING THE REFORMERS: PROTESTANT DEVELOPMENTS
A. Protestant Scholasticism B. The Emergence of Pietism: Jacob Spener B. Worldly Reformers: Puritanism, Jonathan Edwards & the American Experiment C. Reform Within: The Emergency of Methodism, John Wesley
XI. THE GREAT WATERSHED
A. Science and the Enlightenment : Galileo to Newton to the Social
Enlightenment B. Friedrich Schleiermacher: The Beginnings of Modern Theology C. Soren Kierkegaard: The Beginnings of Existentialism D. Liberal Theology: Modernism and the Social Gospel
XII. THE END OF AN EPOCH AND THE BEGINNINGS OF CONTEMPORARY THEOLOGY: K. Barth and the 20th Century

@Krayola2
I look forward to a very enlightening discussion on the topic