Maxentius was a Roman emperor who ruled from 306 to 312 AD, but he was never recognized as a legitimate ruler by his rivals. He was the son of Maximian, one of the two senior emperors in the tetrarchic system established by Diocletian in 293 AD. Maxentius grew up as a crown prince, but he did not hold any significant military or administrative position during his father’s reign.
When Diocletian and Maximian abdicated in 305 AD, they appointed two new senior emperors (Augusti), Constantius and Galerius, and two junior emperors (Caesars), Severus and Maximinus. Maxentius and Constantine, the sons of the former Augusti, were overlooked for the succession. Maxentius retired to his estate near Rome, while Constantine joined his father in Britain.
In 306 AD, Constantius died and Constantine was acclaimed as Augustus by his troops. Galerius reluctantly accepted him as Caesar, but promoted Severus to Augustus. Maxentius, feeling slighted and supported by the Praetorian Guard and the Senate, declared himself princeps (prince) in Rome on October 28, 306 AD. He soon took the title of Augustus and claimed to be the protector of Italy and Africa.
Maxentius faced several challenges to his authority. In 307 AD, Severus marched against him, but was defeated and killed by Maximian, who had returned from retirement to support his son. Maximian then tried to ally with Constantine by offering him his daughter Fausta in marriage and recognizing him as Augustus. However, Maximian and Maxentius soon quarreled and Maximian fled to Constantine’s court in 308 AD.
In 308 AD, Diocletian also came out of retirement and convened a conference at Carnuntum to restore order in the empire. He persuaded Maximian to abdicate again and appointed Licinius as Augustus in the west, while Galerius and Maximinus remained Augusti in the east. Maxentius was declared a usurper and an enemy of the state.
Maxentius did not accept this verdict and continued to rule in Italy and Africa. He tried to win popular support by restoring public buildings, issuing coins with traditional symbols, and granting privileges to the Senate and the pagan priesthoods. He also stopped the persecution of Christians that had been initiated by Diocletian.
However, Maxentius also faced internal dissent and external threats. In 308 AD, his vicar in Africa, Domitius Alexander, rebelled and proclaimed himself Augustus. Maxentius sent his praetorian prefect Rufius Volusianus to suppress the revolt, which he did by 310 AD. In 310 AD, Maximian also attempted to overthrow Maxentius in Rome, but failed and committed suicide.
Meanwhile, Constantine had consolidated his power in Gaul, Britain, and Spain. He decided to challenge Maxentius for Italy in 312 AD. He crossed the Alps with a large army and defeated Maxentius’s forces at Turin, Verona, and Brescia. He then advanced towards Rome, where Maxentius had fortified himself with a huge army.
On October 28, 312 AD, exactly six years after his proclamation, Maxentius met Constantine at the Milvian Bridge over the Tiber river. According to some sources, Constantine had a vision of a cross in the sky with the words “in hoc signo vinces” (“in this sign you will conquer”) before the battle. He ordered his soldiers to paint the chi-rho symbol (☧), a monogram of Christ’s name, on their shields.
The battle was fierce and bloody. Maxentius’s army outnumbered Constantine’s army, but was less disciplined and loyal. Maxentius himself was not a skilled commander and relied on his generals for advice. He decided to retreat across the bridge, hoping to regroup inside Rome. However, the bridge collapsed under the weight of his fleeing troops and he fell into the river and drowned.
Constantine entered Rome as a victor and was welcomed by the Senate and the people. He attributed his victory to the Christian God and issued the Edict of Milan in 313 AD, granting religious tolerance to all faiths. He also completed some of the building projects that Maxentius had started, such as the Basilica of Maxentius (renamed after himself).