Postumus - Rule

Rule

Postumus was immediately recognized as emperor in Gaul (except for Narbonensis), the two Germanias, and Raetia. By 261, Britannia and Hispania had also acknowledged him as emperor. He established his capital at Colonia Claudia Ara Agrippinensium and then proceeded to set up as much of the traditional Roman legislative and executive structures as he could. Apart from the position of emperor, he immediately assumed the office of consul alongside a colleague, Honoratianus. As per his imperial predecessors, he became the pontifex maximus of the state and assumed tribunician power each year. He established a senate and a praetorian guard. Reflecting his power base, the chief members of Postumus’ administration appeared to have been of northern Gallic origin, and indeed, the entire administration soon became rapidly Gallicized. Both Victorinus and Tetricus I, important members of the government, hailed from this region.

Postumus represented himself as the restorer of Gaul (Restitutor Galliarum) and the bringer of security to the provinces (Salus Provinciarum) on some of his coins; prior to 10 December, 261, he also took the title of Germanicus maximus, a title he earned after successfully defending Gaul against the Germans. His principal objective in assuming the purple appeared to be the restoration and defence of the Rhine frontier and the surrounding area, a task that he approached with vigour, earning the admiration of the ancient authors, who declared that he restored the security that the provinces had enjoyed in the past. So successful was he in the task of restoring peace and security to the provinces under his direct control that the coins issued by Postumus were of better workmanship and higher precious metal content than coins issued by Gallienus. After having spent four years pushing the Franks out of Gaul, Postumus then recruited Frankish troops to fight against other Franks, probably dispersed within existing Roman army units.

There is still considerable debate as to what Postumus’ ultimate aims were, whether he ever intended to usurp Gallienus or whether he was content to rule the western provinces. Right from the beginning of his usurpation, Postumus had made it clear that he had no intentions to make a bid for Rome, that his priority was for Gaul. Postumus' powerbase was Gaul and his main responsibility was the defense of the Rhine provinces. If he marched against Gallienus, then he would be exposing his heartland not only to the Germanic tribes but also potentially to any number of usurpers. Perhaps he hoped to achieve some official recognition from Gallienus; what is clear however, is that Postumus had no intention of creating a separate “Galliarum imperium”.

For four years Gallienus had been too distracted by Germanic invasions and other usurpers in the east to turn his attention to the situation to his north and west. This changed in 265 when Gallienus launched a campaign to defeat Postumus. After some initial success against Postumus, his first attempt failed when Postumus managed to escape from a precarious situation due to the carelessness of Gallienus' cavalry commander Aureolus, leading to Aureolus’demotion and eventual abandonment of Gallienus in 267. A second campaign, led by Gallienus himself, also seemed to have the advantage over Postumus, but while Gallienus was besieging a city in Gaul (probably Augusta Treverorum), he was wounded and forced to withdraw. After his failed attempt at defeating Postumus, Gallienus was occupied with crises in the rest of his empire and did not have any further opportunities to challenge Postumus again. Gallienus nevertheless did manage to wrest control of Raetia from Postumus during these years.

By the end of 265, Postumus' coins were proudly announcing his victory over Gallienus, and the festivities celebrating his quinquennalia continued into the following year. Very little troubled the reign of Postumus throughout 267, but a sudden deterioration in the coinage in 268 shows that Postumus was facing increasing difficulties, resulting in the need to buy off an increasingly discontented army.

Nevertheless, Postumus was given a golden opportunity in 268 to move against Gallienus when Aureolus, Gallienus’general who was in command of Mediolanum, openly changed sides and allied himself with Postumus. The city of Mediolanum would have been critical to Postumus if he planned to march on Rome. For whatever reason, Postumus failed to support Aureolus, who was besieged by Gallienus. Before the end of the northern summer in 268, the events at Mediolanum were to see the assassination of Gallienus, the defeat of Aureolus, and the accession of Claudius II. It also triggered a sequence of events that would see the end of Postumus’ rule in Gaul.