[7] The Gallic Empire was established by Postumus in 260 in the wake of barbarian invasions and instability in Rome, and at its height included the territories of Germania, Gaul, Britannia, and (for a time) Hispania.

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.

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.

[11] 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.

[12][13] Victorinus spent most of his reign dealing with insurgencies and attempting to recover the Gaulish territories taken by Claudius Gothicus.

[14] 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 Gothicus's successor Aurelian was in the east fighting the Palmyrene Empire, now in open revolt against Roman authority under Queen Zenobia.

The following year the younger Tetricus 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.

Their names are as follows:[19] Postumus the Younger, Empress Victoria and Victorinus Junior are included as leaders in the list of the Thirty Tyrants, but there are no coins or inscriptions about them.

Victorinus Junior and Postumus the Younger are both now generally considered to be fictional[21][22] while Victoria’s existence was proven by the discovery of her funerary stele in 2012.