Was Constantine really 'Great', or have we believed the lies of a tyrannical despot?
During the early fourth century, a Roman emperor named Constantine defeated his political enemies, put a new order in place across the empire, and claimed that he was 'blessed by God' to rule.
He founded a new capital at Byzantium, made legal the once-persecuted Christian religion, and built a public image of authority based on both military victory and spiritual legitimacy.
For centuries, some religious writers praised him as a saintly figure, but modern research has shown a more disturbing reality beneath imperial titles and the public imagery of marble portraits and golden coins.
Who was Constantine 'the Great'?
Constantine I ruled the Roman Empire from AD 306 to 337 and influenced the empire's religion and politics in ways that outlived him by more than a thousand years.
He reigned for thirty-one years, which made his rule one of the longest of any Roman emperor since Augustus.
His full name was Flavius Valerius Constantinus, which often appeared on inscriptions and coinage across the Roman world, though the title “the Great” gradually became more widely used during the reign of his sons and was popularised in later Christian and praise-filled sources.
He was born around AD 272 in Naissus, a Roman city located in the province of Moesia (modern Niš in Serbia), and his early life took place under the influence of the Tetrarchy.
That political system, which was introduced by Emperor Diocletian, divided imperial authority between two senior emperors, called Augusti, and two junior colleagues, known as Caesars.
Constantine’s father, Constantius Chlorus, became Caesar of the western empire in AD 293 and ruled over Gaul and Britain.
At first, Constantine remained in the eastern court, where he observed imperial politics under Diocletian and his colleague Galerius.
Yet after his father died in Eboracum (York) in AD 306, the legions there declared Constantine emperor, despite official succession procedures that required imperial agreement.
Between AD 306 and 324, Constantine faced multiple rivals for control of the empire, including Maxentius, Galerius, Maximinus Daia, and Licinius, each of whom claimed the right to rule under Diocletian's old system.
His decision to accept the title helped set in motion a long period of civil wars and rival claims that disrupted the balance Diocletian had attempted to impose.
Rise to power
Once his father died, Constantine moved quickly to assert his claim, as he issued coins that showed him in military dress, distributed gifts to his troops, and portrayed himself as a rightful heir who carried on a family lineage.
To strengthen his position, he married Fausta, the daughter of the retired emperor Maximian, and built alliances with powerful families in the west.
By AD 312, he prepared to challenge Maxentius, who held Rome and claimed imperial status without legal recognition.
On 28 October of that year, Constantine’s army defeated Maxentius at the Battle of the Milvian Bridge, where Maxentius drowned in the Tiber after his forces collapsed under pressure.
Later Christian writers, such as Lactantius and Eusebius, had claimed that Constantine received a vision before the battle, which instructed him to place a divine symbol, the Chi-Rho, on his soldiers’ shields.
The Chi-Rho was a monogram that was formed when the Greek letters Χ (Chi) and Ρ (Rho) were superimposed, which stood for the first two letters of “Christos” and became one of the earliest Christian military symbols.
Some modern historians have viewed this story as a later invention designed to justify his victory, but it nonetheless formed Constantine’s future image as a Christian ruler.
The real nature of his time in power
After the Milvian Bridge, Constantine ruled the western half of the empire as sole Augustus, though he continued to face rivals in the east, as his most serious challenge came from Licinius, who controlled the Balkans and Asia Minor and briefly cooperated with Constantine to issue the Edict of Milan in AD 313.
Issued in February AD 313, the Edict of Milan granted tolerance to Christianity, ordered the return of previously confiscated property, and ended legal discrimination against Christians across the empire.
Eventually, their rivalry led to a final clash at the Battle of Chrysopolis in AD 324, where Constantine defeated Licinius and became sole ruler of the entire empire.
Licinius surrendered, but Constantine ordered his execution a year later, claiming that he had plotted rebellion.
Although ancient sources vary on the circumstances, some reported that Licinius had been promised safety.
Constantine’s decision to execute him highlighted his readiness to remove any potential threat to his power.
A few years later, Constantine carried out one of the most shocking decisions of his reign, as in AD 326 he executed his eldest son Crispus, who had enjoyed a successful military career and had once appeared destined to inherit the empire.
The reasons for the execution remain unclear, though some ancient writers implied that accusations of misconduct were made by Fausta, Constantine’s wife.
Soon after, Fausta herself died under unclear circumstances, as some later sources claimed she was suffocated in a heated bath, while others suggested alternative methods or motives.
No official explanation was ever given, and official records gave no explanation.
Meanwhile, Constantine launched major reforms. He introduced the gold solidus, a high-value coin that continued to be the core of Byzantine currency for centuries.
He reorganised the imperial army by increasing the size and role of the comitatenses, mobile field units that could respond rapidly to military threats.
He also moved to bring the imperial court under tighter control and placed family members in high-ranking positions so he could keep direct control over key regions.
Constantine increasingly bypassed the traditional senatorial structures by issuing constitutiones principis, imperial edicts that carried the force of law without needing Senate approval.
In AD 330, he officially opened the city of Constantinople, constructed on the site of the ancient city of Byzantium.
That new capital contained Roman forums, Christian basilicas, and imperial palaces, and it allowed Constantine to distance himself from the senatorial elite of old Rome, whom he distrusted.
The move also shifted imperial focus towards the eastern Mediterranean, where economic and military strength had become increasingly concentrated.
To commemorate his victory at the Milvian Bridge, the Senate dedicated the Arch of Constantine in AD 315, which incorporated sculptural elements taken from monuments of Trajan, Hadrian, and Marcus Aurelius, which connected Constantine’s image with Rome’s past glories.
What influence did Christianity have on Constantine?
At first glance, Constantine’s support for Christianity appeared sincere, yet closer examination suggests that his motives were often political.
He had delayed baptism until shortly before his death, had maintained traditional religious titles such as Pontifex Maximus, and had continued to issue coins that featured Sol Invictus, a solar deity linked to imperial power.
His mother was Helena, who had converted to Christianity, and she made a pilgrimage to the Holy Land around AD 326 and had been credited with discovering the True Cross.
Even so, Constantine gave increasing support to the Christian clergy and used Church structures to enforce social order.
For instance, he granted bishops the right to hear legal disputes, funded major building projects for Christian communities, and returned confiscated Church property.
Constantine sponsored the construction of several large-scale Christian churches, such as the original St. Peter’s Basilica in Rome, the Church of the Holy Sepulchre in Jerusalem and the Church of the Nativity in Bethlehem.
His promotion of Christianity strengthened his reputation among the growing Christian population, especially in urban centres across the eastern empire.
In AD 325, he convened the First Council of Nicaea, where bishops debated the teachings of Arius, a priest who argued that Christ was subordinate to God the Father.
The outcome of the council, the Nicene Creed, rejected Arianism and expressed an agreement on doctrine, although controversy persisted for decades.
Although Constantine lacked formal theological training, he viewed religious unity as essential for political stability, and he treated opposition as a political challenge to imperial order.
Later, he restored some Arian clergy and exiled bishops who opposed his religious settlements, which suggested that his concern lay less with doctrine and more with harmony under imperial authority.
His approach to religion resembled his broader approach to power, as he treated religious disagreement as a political threat and relied on central institutions to impose uniformity and discipline.
How much of this story can we trust?
The most detailed source on Constantine’s life was Vita Constantini by Eusebius of Caesarea, which shows the priorities of Christian imperial propaganda rather than objective reporting.
Written after Constantine’s death, it described the emperor as a holy man chosen by God, who banished demons and protected the Church.
Eusebius had ignored the deaths of Crispus and Fausta, had praised Constantine’s military campaigns in glowing terms, and had claimed divine intervention in almost every major decision.
Other Christian sources such as Lactantius’ On the Deaths of the Persecutors also presented Constantine as a divinely favoured liberator.
They described his victory over Maxentius as a triumph of good over evil and painted his opponents as cruel pagans.
By contrast, non-Christian writers including Zosimus in the fifth century condemned Constantine’s rule as disastrous.
Zosimus accused him of weakening the empire by undermining traditional religion, abandoning Rome, and promoting officials based on loyalty rather than merit.
Physical evidence shows another side, as coins, monuments and inscriptions largely confirmed many of Constantine’s actions, such as his founding of Constantinople and his religious patronage.
Yet they also showed how carefully he crafted his public image. For example, imperial coins from different regions depicted him as either a Christian leader, a soldier-emperor, or a divine ruler, which varied according to the audience.
Today, historians increasingly approach Constantine’s reign with greater scepticism.
While he undoubtedly transformed the empire, many scholars argue that his success largely derived from political skill, violent suppression and the use of religious feeling to influence people rather than from moral greatness.
Constantine died on 22 May AD 337 near Nicomedia, possibly in the suburb of Ancyrona, and was buried in the Church of the Holy Apostles in Constantinople.
That site, which some Christian writers later interpreted as including symbolic tombs for the twelve apostles alongside Constantine himself, was designed to reinforce his image as God's chosen ruler.