Constantine’s Conversion: A Unifying Factor for Rome?


By Bart D. EhrmanThe University of North Carolina, Chapel Hill

Scholars since the 19th century have questioned whether Constantine’s conversion to Christianity was genuine or a political ploy. We have several records from Constantine’s own day by authors in his empire who knew him, and who independently attested that he committed himself to the Christian faith sometime before the Battle of the Milvian Bridge in October 312. But did he actually convert?

Portrait of the Battle of The Milvian Bridge
Constantine supposedly converted to Christianity before the Battle of the Milvian Bridge. (Image: Charles Le Brun/Public domain)

The Roman Empire

In the view of the skeptics, Constantine’s conversion was a front. Constantine recognized where the Christian church was going, and he jumped on the bandwagon, realizing the enormous political benefits that could result, much as some modern political figures claim to be believers but show zero evidence of it.

Isn’t it possible that Constantine, ruling over a highly fractured empire, saw the utility in promoting a religion focused entirely on unity? The empire had long been fragmented. How could he bring it together? Religion can be a powerful political tool, but paganism was massively diverse. 

Surely it would help if all people worshiped one God, not many. God, who is the one sovereign over all the world, who had one son who provided one way of salvation to all people of every kind, who had to join the one church to become part of the one people of God.

Moreover, this one God in heaven authorized one ruler on earth. To paraphrase Paul’s letter to the Ephesians, there was one lord, one faith, one baptism, and one emperor. The one God rules from heaven above, and his chosen emperor rules on earth below.

All this seems plausible. But history cannot be written based simply on intuition and basic common sense. A lot of things happen that may not seem to make sense. One has to consider the evidence. Otherwise, it’s an uninformed opinion, not history.

What Is a Christian?

To begin our exploration of the authenticity of Constantine’s conversion, let’s return to the question of what it actually means to say that someone in antiquity converted to Christianity. We’re using the term conversion in a broad sense, simply to mean a decided shift from one set of religious practices and beliefs to another.

Saying that the Apostle Paul converted means that he completely changed his views of Christ away from thinking that Christ was a low-life criminal crucified for crimes against the state to thinking he was the son of God who died for the sins of the world. Paul’s conversion was not from Judaism to a different religion but to a new understanding of the Judaism he had been raised with.

Committed to One God

Most converts to Christianity did shift from one kind of religion to another, from paganism to Christianity. It’s important to remember that we’re using a broad definition of the term Christian as well. We’re not defining Christianity in one narrow, specific way, saying that a person has to subscribe to one particular set of theological beliefs or engage only in specific ethical types of behavior, or else they are not really Christian. 

That certainly is how many people today talk about their own Christian faith. But from an outside perspective, Bible-thumping fundamentalists, Roman Catholics, Russian Orthodox, and Mormons are all simply different kinds of Christian. For the ancient world and our purposes, a Christian is anyone who is committed to worshiping the God of Jesus and seeing Christ as the way of salvation. There will be fuzzy lines, of course, and difficult-to-decide cases.

This article comes directly from content in the video series The Triumph of ChristianityWatch it now, on Wondrium.

Constantine the Pagan

Constantine shifted from worshiping the Balkan gods of his homeland, the Roman state gods, and the gods of the army and his family to worshiping the one God of the Christians, maintaining that Christ alone could bring salvation.

What we can say for certain is that when he at least announced his change of allegiance, he probably had no idea what he was actually getting into. Constantine may not have known that as a Christian, he would have to be baptized.

That had been a sacred rite for Christians for a very long time, going back to the New Testament itself. But there is good reason to think that Constantine converted long before he knew anything about the Christian scriptures or obligatory rituals.

It Might Have Been Strange to Him

Mosaic of Constantine
Even if Constantine’s empire wasn’t the reason behind his conversion, he couldn’t have known everything about Christianity until after converting. (Image: Byzantine mosaicist/Public domain)

He may not have known that there were certain theological beliefs that his spiritual advisers would insist that he subscribed to. Some of these beliefs were highly controversial even within the Christian tradition. And even later, Constantine was apparently not completely cognizant of all the niceties and nuances. Like many others who came into the church before knowing a lot about it, it’s easy to imagine him telling his Christian instructors, “I’m supposed to believe what?”

Constantine certainly didn’t know anything about the theological quagmires he was very soon to find himself immersed in, with earth-shattering subtleties that he found trivial and even a bit absurd. He may also not have known anything about the ethical expectations of this new faith. 

Many pagan converts may well have been shocked by strict Christian moralists who were avidly opposed to abortion, serving in the military, or even wearing makeup. But at some point, possibly after a long period of transition, Constantine shifted from being a pagan to being a Christian.

Common Questions about Constantine’s Conversion and an Empire in Need of a Unifying Religion

Q: What do skeptics think of Constantine’s conversion to Christianity?

Skeptics believe that Constantine’s conversion was a political ploy to grant him more power than before. He was intelligent enough to see what path the church was taking, and he jumped at the chance he had and followed. Constantine‘s empire could have benefited from a unifying religion.

Q: What the Constantine worship before converting to Christianity?

Constantine‘s empire included pagan religions like worshiping the Balkan gods, the Roman state gods, and the gods of the army and his family. Constantine worshiped these just like everybody else until he converted to Christianity.

Q: How much did Constantine understand about Christianity before his conversion?

Constantine may not have known about some of the finer aspects of the religion, such as theological beliefs that his advisors would have him subscribe to or subtle but controversial differences in theological arguments.

Keep Reading
What Motivated the Pagans to Follow Christianity?
Growth of Christianity: An Impact of Alleged Miracles?
Christianity: How Miracles and Conversions Were Related