The Arch of Constantine stands in Rome beside its more famous companion, the Colosseum. It is remarkably well preserved, largely because it was incorporated into a medieval fortress. Decorated with more reliefs and statues than any other surviving Roman structure, it is also deeply mysterious. For example, why, like a time traveller, does it display unrelated figures collected over a two hundred year time-span attributable to the reigns of four quite different emperors - Trajan, Hadrian, Marcus Aurelius and Constantine? And why, when it was supposedly built to celebrate one of Christianity’s most important historical landmarks - Constantine’s victory at the Battle of the Milvian Bridge in AD 312, when he converted to Christianity - does it display no Christian symbols or signs whatsoever?
What secret is it hiding?
The mystery has long baffled historians. No definitive answer has ever been found. Yet, I suggest this is because we have been looking in the wrong place. The secret to Constantine’s arch lies not in the polemical narrative written by the early Christian church but in its true historical context. And that context was one of the strangest times in history. For it was fashioned at a time of seismic change within the Roman Empire. A time when the empire had just survived a cataclysmic assault on its frontiers in an age often referred to as ‘the crisis of the third century’. However, because of the scarcity of surviving records, this crisis is hardly ever talked about or its true historical significance appreciated.
In my forthcoming book called ‘The Roman Revolution’ (publication July 2022 by Puttenham Press), I describe the horrors of the third century, when most of the empire was overrun by Germanic barbarians and the heavily armoured cavalry regiments of Persia. It was the fall before the final fall of Rome in the fifth century, when Alaric the Goth sacked the Eternal City in AD 410. Yet, in the third century, Rome did not fall. It was saved by a new breed of emperor. These were professional soldiers risen from the ranks, who seized control of the empire, wresting it from the corrupt and indolent Roman senate. Soldier-emperors, like Aurelian and Diocletian, fought Rome’s enemies to a standstill and then turned them back. It was the greatest conflict in the ancient world. I estimate that in twenty years, from AD 250 to 270, well over a quarter of a million Roman soldiers were killed in battle. Their enemies suffered even higher casualties. In the end, the Romans won. But the cost was enormous. The Roman Empire was never the same again.
In brief, that is the answer to the mysteries of Constantine’s arch. For it does not represent the usual imperial triumphalism displayed in other Roman monuments. Instead, it is a hastily gathered collection of statues and reliefs taken from an earlier age - the long forgotten days of Trajan, Hadrian and Marcus Aurelius augmented with a few primitive carvings to commemorate Constantine’s victory (see picture below of the crude sculpture of Constantine (headless) dispensing money to his people). For by the fourth century, the Romans no longer possessed the artistic skills of their forefathers and hence Constantine’s arch could only be decorated with trophies taken from older buildings in Rome.
Constantine (head removed in later centuries) sits distributing money to his people, as carved somewhat primitively on the Arch of Constantine
But what about Christianity? The answer is that one of the most enduring legacies of the crisis of the third century was the growth of Christianity. Faced with a near death experience, the Romans rejected their traditional gods. Jupiter and Hercules were replaced by an altogether more humble and sympathetic figure - as befitted the new condition of the Roman Empire - in the form of the caring and forgiving Jesus Christ.
So, why does the arch not contain Christian symbols since the greatest of all early Christian chroniclers, Eusebius and Lactantius, say that the emperor Constantine personally told them that he converted to Christianity on the eve of the battle of the Milvian Bridge? The answer lies with a clever cover-up. Yes, Constantine did convert to Christianity but it is very likely that this was at a much later date in his reign, and for political reasons that made sense at the time - i.e. his opportunity to take the helm of a growing new religion (for more details see my book). In all probability, he simply made up the stories of his earlier conversion for a Christian audience that was all too willing to lap it up.
In fact, the evidence firmly points to his being a pagan in AD 312, and more specifically a follower of a Roman sun god called Sol. Indeed, such is shown clearly engraved on the Arch of Constantine (see picture below) and explains the absence of any Christian symbols. The worship of Sol was hugely popular at that time, especially in the Roman army, and it makes compelling sense that, to begin with at least, Constantine’s faith was no different from that of the majority of his ordinary soldiers. Reinforcing this link to Sol, some historians believe the arch was lined up with the gigantic statue which Nero had originally installed outside the Colosseum, and which had been re-dedicated to Sol by both Vespasian and Hadrian.
The sun god Sol is depicted riding his chariot on the Arch of Constantine So, perhaps the mysteries of Constantine’s arch are not so mysterious after all.
The answers lie with understanding an age that was much more complex than might be supposed. And one that, with its tangled web of war, despair and hope, was so much more human and believable than that presented by the early Christian chroniclers.