After successfully revolting against Gallienus in 260, Postumus established a separate empire in the West. It consisted mainly of Gaul, Britain, Spain, and the northern German provinces.  His control of mining operations in Britain and Spain financed the enterprise. He fought successful campaigns against the Franks and Alamanni from Germany, and twice foiled attempts by the Emperor Gallienus to dislodge him. It is unclear whether he ever intended to expand his empire into Italy and the East, or remained satisfied with controlling the West only. After quelling a revolt by Laelian he was murdered by mutinous soldiers at Mainz in AD 269.

The date of the revolt of Laelian and the duration of his brief reign are much disputed. His revolt lasted from approximately late February to early June AD 269. Laelian may have been a descendant of the noble Spanish family of the Ulpii, who numbered the Emperor Trajan among its ancestors. He was eventually besieged at Mainz by Postumus and executed.

According to ancient tradition Marius began life as a blacksmith.  He rose through the ranks in the army, and following the murder of Postumus the army elected him as successor. In gratitude he allowed the army to sack Mainz, but his reign lasted no more than two or three months before Postumus' Praetorian Prefect, Victorinus, asserted his own control and Marius perished, allegedly by a blade of his own forging.

A native of Gaul and from a wealthy family, Victorinus, had risen under Postumus to be Praetorian Prefect and co-consul. His reign was essentially a long rear-guard action against the resurgent Roman Empire's attempts to re-absorb the breakaway provinces; Spain had never accepted his rule. He was murdered at Cologne by an officer whose wife he is alleged to have seduced.

Domitian was probably an officer in the army of Victorinus, who was acclaimed Emperor, probably in Northern Gaul in late 270 or early 271. He is probably the ‘Domitianus’ who is twice mentioned in the sources as a significant figure in the politics of the age, but not as a contender for the throne. His brief rebellion is attested by only two surviving coins.

The last of the Gallic Emperors. Tetricus I was a wealthy senator from a noble Gallic family. He was acclaimed Emperor by the army following the murder of Victorinus. He was forced to repel invasions of Germanic tribes across the Rhine. He was recognised in Gaul and Britain, but rebellions soon began against his rule, and, from AD 273, the new Roman Emperor, Aurelian, set out to reconquer Gaul. Eventually Tetricus surrendered to Aurelian, and in return his life was spared and he lived out his life in obscurity in southern Italy.

Son of Tetricus I, he was associated in his father’s reign as his Caesar.