Editing Gallic Empire (section)

===Origins===
The Roman [[Crisis of the Third Century]] continued as the Emperor [[Valerian (emperor)|Valerian]] was defeated and captured by the [[Sasanian Empire]] of [[Persia]] 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, the [[Palmyra|Palmyrene]] leader [[Odaenathus]] gained control of a wide swath of the east, including [[Roman Egypt|Egypt]], [[Roman Syria|Syria]], [[Iudaea Province|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. The Emperor left for the Danube to attend to their disruption. This left [[Postumus]], who was governor of [[Germania Superior]] and [[Germania Inferior|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 would be 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.

[[File:Map of the Gallic Empire, 260 AD.jpg|342px|thumbnail|The Gallic Empire at its greatest territorial extent, after its creation by [[Postumus]] in 260]]

Gallienus's son [[Saloninus]] and the praetorian prefect Silvanus remained at [[Colonia Agrippina]] ([[Cologne]]), to keep the young heir out of danger and perhaps also as a check on Postumus' ambitions. Before long, however, Postumus besieged Colonia Agrippina and put the young heir and his guardian to death, making his revolt official. Postumus is thought to have established his capital there or at [[Augusta Treverorum]] ([[Trier]]).{{sfn|Drinkwater|1987|pp=24-27}} [[Lugdunum]] ([[Lyon]]) 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 [[Consul (Gallic Empire)|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 [[Roman Mogontiacum|Mogontiacum]] (now [[Mainz]]) 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.<ref>[[Aurelius Victor]] 33.8.</ref><ref>[[Eutropius (historian)|Eutropius]] 9.9.1.</ref>