Europe 307: Galerius vs Maxentius
Galerius rejected Maxentius’ claim to power in Rome and sent Severus to crush him in early 307. However, Maxentius’ father Maximian returned in support of his son and the two defeated Severus. Maximian then traveled to Gaul to secure the friendship of Constantine. While he was doing this, Galerius invaded Italy himself, but had to withdraw when he realized he could not capture Rome.
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.
Mar–Apr 307 Severus II vs Maxentius▲
Galerius refused to recognize Maxentius as emperor and sent Valerius Severus 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.
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.
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.
Sep 307 Constantine and Fausta▲
In a bid to secure his and his son’s rule, Maximian traveled to Gaul to meet with Constantine in the late summer of 307. That September Constantine married Maximian’s youngest daughter Fausta and Maximian conferred on Constantine the title of Augustus. Despite this, Constantine did not formally break with Galerius, preferring to maintain ties with both factions.