Eastern Mediterranean 307: Galerius vs Maxentius

When the Western Augustus Constantius died in July 306, his son Constantine was proclaimed as his successor by the troops. The Eastern Augustus Galerius reluctantly acknowledged Constantine, but as a Caesar, and instead promoted Valerius Severus to the position of Western Augustus. Feeling spurned, Maxentius, the son of Constantius’ predecessor Maximian, took advantage of dissent in Italy and seized power in Rome. With the help of his father, Maxentius then overthrew Severus and defeated Galerius’ attempt to invade Italy.

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Main Events

25 Jul 306 Accession of Constantine I ▲

Following Constantius Chlorus’ promotion to Augustus in May 305, his eldest son Constantine was released from the court of Galerius and raced west, meeting Constantius at Bononia (Boulogne) as he was about to depart for Britain. The two campaigned against the Picts together, when Constantius fell ill, dying at Eboracum (York) on 25 July 306. The troops immediately rallied behind the 34-year-old Constantine, proclaiming him emperor in his father’s place. in wikipedia

306 Third Tetrarchy ▲

When Galerius learned of Constantius Chlorus’ death, he promoted Valerius Severus to Augustus in the West but initially refused to acknowledge Constantine’s accession to power in Gaul. However, after it became clear that the Gallic legions firmly supported Constantine, Galerius backed down and acknowledged him as Caesar, but emphasized Severus’ seniority by giving the latter authority over the dioceses of Hispaniae and Pannoniae. in wikipedia

28 Oct 306 Maxentius’ Coup ▲

In 306 Galerius, as senior Augustus, attempted to end Rome’s tax exempt status and reduce the size of the Praetorian Guard, provoking dissent in what was still the imperial capital. After killing several officials, the Praetorians found Maxentius, the twenty-something son of the former Augustus Maximian and son-in-law of Galerius, at his villa and proclaimed him emperor. Maxentius, bitter at being passed over for leadership earlier, accepted the title of Princeps, possibly hoping that Galerius would acknowledge him as had happened with Constantine. in wikipedia

Oct–Nov 306 Maxentian Revolt ▲

Maxentius’ coup in Rome quickly gained support across Italy south of the Po, as well as the islands of Corsica, Sardinia, and Sicily. When news of the revolt reached Valerius Alexander in Carthage, he too immediately declared for Maxentius—it is possible that the government of Africa still retained loyalty to Maxentius’ father Maximian, who had successfully campaigned there in 297–8. in wikipedia

Mar–Apr 307 Severus II vs Maxentius ▲

Galerius refused to recognize Maxentius as emperor and sent Severus II to crush him. Gathering a number of legions in Mediolanum, Severus invaded Italy, but was undone when most of his army deserted him. Fleeing north, Severus took refuge in Ravenna, only to be tricked into surrendering to Maxentius and imprisoned. in wikipedia

307 Return of Maximian ▲

When it became clear that Galerius and Valerius Severus were moving to crush him, Maxentius called on his father Maximian—who had retired to Campania after stepping down as Augustus—for support. Maximian returned to Rome in 307, where his presence helped persuade Severus’ Moorish troops, most of whom had previously served under him (Maximian), to defect. Supported by the legions and the Senate, Maximian was once again proclaimed Augustus, a rank also granted to his son Maxentius a few months later. in wikipedia

Sep–?? 307 Galerius vs Maxentius ▲

While Maximian was in Gaul negotiating with Constantine, Galerius launched an invasion of Italy and advanced to the gates of Rome, prompting a panicked Maxentius to execute the captive Valerius Severus. However, the immense size of the city apparently astounded Galerius, who had never visited it before, and he soon realized he lacked the forces to capture it. With winter approaching, his troops low on morale, and the population hostile, the emperor was forced to withdraw from the peninsula and admit defeat. in wikipedia