Europe 306: Constantine and 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.
?? 305–Jan 306 Constantius I’s Pictish Campaign▲
In the summer or fall of 305, Constantius Chlorus and his son Constantine traveled from Gaul to Britain to deal with Pictish incursions. Constantius seems to have advanced beyond Hadrian’s Wall, possibly as far north as Dumfries and Galloway, where won a significant victory over the Picts. As a result he was awarded a second title of Britannicus maximus by January 206.
305–307 Sarmatian War of 305–7▲
In 305–6, and again by early 307, Galerius was credited with winning two major victories over the Sarmatians. It is possible that these victories were actually won Valerius Severus—who seems to have spent the period based at Siscia—with only occasional support from Galerius. Severus’ presence on the Danube at this time may also explain why he was unable to respond quickly to Maxentius’ revolt in October 306.
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.
306–307 Ascaric and Merogais▲
While Constantius and Constantine were in Britain, Frankish raiders led by the kings Ascaric and Merogais crossed the Rhine into Gaul. Constantine returned in the summer of 306 and, after defeating the invaders, sent the two kings to face the beasts in the arena at Treverorum Augusta (Trier).
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.
306? Limesfall II▲
During the 270s, under Aurelian and Probus, the Romans had reestablished control in at least some of the forts of the Agri Decumates. This presence lasted until the 290s or 300s, when the Roman military seems to have definitively abandoned the region. By about 310 the Alemanni were becoming the dominant population, although scattered Roman settlements seem to have persisted, and continued to trade with the empire, until about the mid 4th century.
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.