Under Maxentius he was banished from Rome in 309 on account of the tumult caused by the severity of the penances he had imposed on Christians who had lapsed under the recent persecution.

According to this version, the pope was required by Maxentius, who was enraged at his reorganization of the Church, to lay aside his episcopal dignity and make an offering to the gods.

His pontificate lasted only from 18 April to 17 August, after which, in consequence of disturbances within the Church which led to acts of violence, he was banished by the emperor Maxentius, who had been the ruler of Rome since 306, and had at first shown himself friendly to the Christians.

Maximian was to retire, and Maxentius was declared an usurper.

Maxentius was defeated by Constantine at the Battle of the Milvian Bridge in 312 and subsequently killed.

After the usurper Maxentius declared himself Caesar, Augustus Flavius Valerius Severus | Severus marched on Rome but was defeated when his troops deferred to Maxentius.

In Rome, the favorite was Maxentius, the son of Constantius ' imperial colleague Maximian, who seized the title of emperor on 28 October 306.

But whereas Constantine's claim was recognized by Galerius, ruler of the Eastern provinces and the senior emperor in the empire, Maxentius was treated as a usurper.

He easily overran northern Italy, winning two major battles: the first near Turin, the second at Verona, where the praetorian prefect Ruricius Pompeianus, Maxentius ' most senior general, was killed.

It was expected that Maxentius would remain within Rome and endure a siege, as he already had successfully employed this strategy during the invasions of Severus and Galerius.

Holding it was crucial if Maxentius was to keep his rival out of Rome, where the Senate would surely favour whoever held the city.

Constantine's infantry then advanced, most of Maxentius's troops fought well but they began to be pushed back toward the Tiber ; Maxentius decided to retreat and make another stand at Rome itself ; but there was only one escape route, via the bridge.

Maxentius was among the dead, having drowned in the river while trying to swim across it in a desperate bid to escape or, alternatively, he is described as having been thrown by his horse into the river.

Lactantius describes the death of Maxentius in the following manner: " The bridge in his rear was broken down.

Maxentius ' body was fished out of the Tiber and decapitated.

After the ceremonies, Maxentius ' disembodied head was sent to Carthage as proof of his downfall, Africa then offered no further resistance.

Maxentius was condemned to damnatio memoriae, all his legislation was invalidated and Constantine usurped all of Maxentius ' considerable building projects within Rome, including the Temple of Romulus and the Basilica of Maxentius.

In the region of Saints Gaius and Eusebius are some crypts set apart, opposite each other, with the tombs of Pope Gaius ( with an inscription ) and Pope Eusebius, who died in Sicily where he had been exiled by Maxentius and whose body was translated to Rome during the pontificate of Militiades ; on a marble copy of the end of the 4th century ( of which fragments may be seen on the opposite wall ) may be read of an inscription by Damasus on the schism provoked by Heraclius over the matter of the lapsi.

Constantius's marriage to Theodora produced a daughter, Constantia, who married Licinius ; his first marriage to Helena produced a son, Constantine, whose second wife was Fausta, sister of Maxentius and daughter of Maximian.

Constantius I " Chlorus " married twice ; his first wife St. Helena bore him a son, Constantine I whose second wife Fausta ( daughter of Maximian and Eutropia ; sister of Maxentius ; half-sister of Constantius I's second wife Theodora ) bore him three sons ( Constantine II, Constantius II, and Constans I ) and two daughters ( Constantia and Helena ); these children were nieces and nephews of Maxentius, half-nieces and half-nephews of Licinius ( who had married their father's half-sister ), and grandchildren of Maximian.

In preparation for their future roles, Constantine and Maxentius were taken to Diocletian's court in Nicomedia.

Constantius succeeded Maximian as Augustus of the West, but Constantine and Maxentius were entirely ignored in the transition of power.

Diocletian and Maximian were both present on 11 November 308, to see Galerius appoint Licinius to be Augustus in place of Severus, who had died at the hands of Maxentius.

By 308 there were therefore no fewer than four claimants to the rank of Augustus ( Galerius, Constantine, Maximian and Maxentius ), and only one to that of Caesar ( Maximinus ).

This agreement proved disastrous: by 308 Maxentius had become de facto ruler of Italy and Africa even without any imperial rank, and neither Constantine nor Maximinus — who had both been Caesares since 306 and 305 respectively — were prepared to tolerate the promotion of the Augustus Licinius as their superior.

By 312, however, Constantine and Maxentius were engaged in open hostility with one another, although they were brothers-in ‑ law through Constantine's marriage to Fausta, sister of Maxentius.

The hand of the Lord prevailed, and the forces of Maxentius were routed.

Maxentius ' strongest supporters in the military were neutralized when the Praetorian Guard and Imperial Horse Guard ( equites singulares ) were disbanded.

Although prior to 303 there appeared to be tacit agreement between the Tetrarchs that Constantius ’ s son, Constantine and Maximian ’ s son Maxentius were to be promoted to the rank of Caesar once Diocletian and Maximian had resigned the purple, by the end of 304 Galerius had convinced Diocletian ( who in turn convinced Maximian ) to appoint Galerius ’ s nominees Severus and Maximinus Daia as Caesars.

Although with Constantine and Maxentius two sons of emperors were available, they were left out from the new tetrarchy, and Severus and Maximinus Daia were appointed Caesars.

Many buildings in Rome that are commonly associated with Constantine, such as the great basilica in the forum Romanum, were in fact built by Maxentius.

" Panella notes that the insignia were likely hidden by Maxentius ' supporters in an attempt to preserve the emperor's memory after he was defeated at the Battle of Milvian Bridge by Constantine.

The emperor arranged for a plethora of the best pagan philosophers and orators to dispute with her, hoping that they would refute her pro-Christian arguments, but Catherine won the debate and succeeded in converting all of them to Christianity, for which the philosophers and orators were executed by an enraged Maxentius.

Catherine was then scourged and put in prison, during which time over two hundred people came to see her, including Maxentius ' wife the empress, all of whom converted to Christianity and were therefore martyred.

Following the victory of Constantine I over Maxentius ( for whom the Equites singulares augusti had fought ) at the Battle of the Milvian Bridge, the guard were abolished and the fort demolished.

Parts of the wall were doubled in height by Maxentius, who also improved the watch-towers.

Constantine I | Constantine joined the secessionist alliance by marrying Maximianus ' daughter, Fausta, and by supporting Maxentius in Italy.

* October 28 – Maxentius, son of the former Western Emperor Maximian, joins a revolt by the Praetorian Guard in Rome, and is proclaimed Emperor.

Probably the most splendid Roman basilica ( see below ) is the one begun for traditional purposes during the reign of the pagan emperor Maxentius and finished by Constantine I after 313 AD.

Tres Tabernae was the place where the former Emperor Flavius Valerius Severus was held prisoner by Maxentius and Maximian, before being killed ( 307 ).

He was trusted enough by Galerius that in 307 he was sent as an envoy to Maxentius in Italy to attempt to reach some agreement about his illegitimate status.

In one extant inscription ( CIL III. 12132, from Arycanda ), the cities of Lycia and Pamphylia asking for the interdiction of the Christian cult, Maximinus, in another inscription, replied by expressing his hope that " may those [...] who, after being freed from [...] those by-ways [...] rejoice snatched from a grave illness ". After the victory of Constantine over Maxentius, however, Maximinus, according to Eusebius, directed a letter to the Praetorian Prefect Sabinus, in which he expressed the view that it was better to " recall our provincials to the worship of the gods rather by exhortations and flatteries ".

Maxentius refrained from using the titles Augustus or Caesar at first and styled himself princeps invictus ( Undefeated Prince ), in the hope of obtaining recognition of his reign by the senior emperor Galerius.

While negotiating with the invader, Maxentius could repeat what he did to Severus: by the promise of large sums of money, and the authority of Maximian, many soldiers of Galerius defected to him.

Some time during the invasion, Severus was put to death by Maxentius, probably at Tres Tabernae near Rome ( the exact circumstances of his death are not certain ).

Constantine, in an attempt to prevent Maxentius from forming a hostile alliance with Licinius, forged his own alliance with the man over the winter of 311 – 12 by offering to him his sister Constantia in marriage.

While he was not counted under the persecutors of the Christians by early sources like Lactantius, under the influence of the official propaganda later Christian tradition framed Maxentius as hostile to Christianity as well.