Origins The Roman
Crisis of the Third Century continued as Emperor
Valerian was defeated and captured by the
Sasanian Empire in the
Battle of Edessa, together with a large part of the Roman field army in the east. This left his son
Gallienus in very shaky control. Shortly thereafter, King
Odaenathus gained control of a wide swath of the east, including
Egypt,
Syria,
Judea, and
Arabia Petraea; while he was nominally loyal to the Roman government, his domain was
de facto independent and has come to be referred to as the
Palmyrene Empire. The governors in
Pannonia staged unsuccessful local revolts. Gallienus left for the
Danube to attend to their disruption. This left
Postumus, who was governor of
Germania Superior and
Inferior, in charge at the
Rhine border. An exceptional administrator, Postumus had also ably protected Germania Inferior against an invasion led by the
Franks in the summer of 260. In fact, Postumus defeated the Frankish forces at
Empel so decisively that there were no further Germanic raids for ten years. This all combined to make Postumus one of the most powerful men in the western reaches of the Roman Empire. in 260 Gallienus's son
Saloninus and the praetorian prefect
Silvanus remained at
Colonia Agrippina to keep the young heir out of danger and perhaps also as a check on Postumus' ambitions. In 260 Postumus besieged Colonia Agrippina and put Saloninus and Silvanus to death, making his revolt official. Postumus is thought to have established his capital there or at
Augusta Treverorum.
Lugdunum was one of the most important cities in the area under his control. Postumus did not make any effort to extend his control into Italy or to depose Gallienus. Instead, he established parallel institutions modelled on the Roman Empire's central government: his regime had its own
Praetorian Guard, two annually elected
consuls (not all of the names have survived), and probably its own
senate. According to the numismatic evidence, Postumus held the office of consul five times. Postumus successfully fended off a military incursion by Gallienus in 263 and was never challenged by him again. However, in early 269 he was challenged by
Laelianus, who was probably one of his own commanders. Laelianus was declared emperor at
Mogontiacum by his
Legio XXII Primigenia. In response, Postumus quickly retook Mogontiacum, and Laelianus was killed. In the aftermath of the battle, however, Postumus was overthrown and killed by his own troops, reportedly because he did not allow them to sack the city.
After Postumus , last emperor (271–274) of the Gallic Empire An officer in Postumus' army,
Marcus Aurelius Marius, was installed as emperor upon Postumus's death, but he died very shortly after; ancient sources writing much later state that he reigned only two days, though it is more likely, based on the numismatic record, that he reigned for a few months. Subsequently, the tribune of the praetorians
Marcus Piavonius Victorinus came to power, being recognized as emperor in northern Gaul and Britannia but not in Hispania. Victorinus spent most of his reign dealing with insurgencies and attempting to recover the Gaulish territories taken by Claudius. He was assassinated in 271, but his mother
Victoria took control of his troops and used her power to influence the selection of his successor. Tetricus fought off Germanic barbarians who had begun ravaging Gaul after the death of Victorinus and was able to re-take Gallia Aquitania and western Gallia Narbonensis while Claudius' successor
Aurelian was in the east fighting the Palmyrene Empire, which was in open revolt against Roman authority under Queen
Zenobia. Tetricus established the imperial court at Trier, and in 273 he elevated his son
Tetricus II to the rank of
caesar. The following year Tetricus II was made co-consul with his father, but the area under their control grew weak from internal strife, including a mutiny led by the usurper
Faustinus. By that time Aurelian had defeated the Palmyrene Empire and had made plans to reconquer the west. He moved into Gaul and defeated Tetricus at the
Battle of Châlons in 274. According to some sources, Tetricus offered to surrender in exchange for clemency for him and his son before the battle. This detail may be later propaganda, but either way Aurelian was victorious, and the Gallic Empire was effectively ended. In contrast with his propaganda after the recent defeat of Zenobia, Aurelian did not present his recapture of Gaul as a victory over a foreign enemy, and indeed many officials who had served in the army and administration of the Gallic Empire continued their careers, including Tetricus, who was appointed to an administrative post in Italy. ==Causes==