Marcus Aurelius Mausaeus Carausius (d. 293) was a Roman imperial usurper in Britain and northern Gaul (286–293).

Carausius was a Menapian who had proven his ability during Maximian's campaign against the Bagaudae rebels in Gaul in 286. As a result, he was appointed to command a navy based in the English Channel with the responsiblity of eliminating Frankish and Saxon pirates who had been raiding the coast. Apparently, however, Carausius adopted the practice of keeping captured treasure for himself and using it to recruit former pirates into his own fleet. Due to this practice, Maximian came to regard Carausius as a threat and ordered his execution. Carausius learned of this and responded by declaring himself Emperor, winning the alliegance of the three legions based in Britain, as well as one in northern Gaul.

Quite how he was able to win support from the army when his command had been sea-based is uncertain. It may be connected with the emperor's assumption of the title Britannicus Maximus in 285, possibly connected with an otherwise unrecorded victory there in which Carausius was instrumental. Two Romano-British towns show signs of destruction from this time and may be connected with an unrest.

With the loyalty of these legions and control of his fleet, as well as the support of the Franks and Britons, Carausius was in a strong position. Maximian was busy with wars on the Rhine and was unable to begin planning an invasion until late 288.

In 289, an invasion of Britain intended to dislodge him failed badly due to storms, although a naval defeat is also possible. An uneasy peace continued until 293 during which Rome prepared for a second effort to retake the province and Carausius began to entertain visions of legitimacy and official recognition. He minted his own coins and brought their value in to line with Roman issues as well as acknowledging and honouring Maximian and then Diocletian. Coinage is the main source of information about the rogue emperor; his issues were initially crude but soon became more elaborate and were issued from mints in London, Rouen and a third site, possibly Colchester. A milestone from Carlisle with his name on it suggests that the whole of Roman Britain was in Carausius' grasp.

It has been speculated (namely, by the historian S.S. Frere ) that the rebellion of Carausius endangered Diocletian's vision of a strong, centralized government based on his tetrarchy. In any case, by early 293 Constantius Chlorus had gained control of northern Gaul, including the rebel's stronghold and port of Boulogne, on which Carausius was heavily dependent. Constantius built a mole across the harbour mouth to ensure it did not receive maritime aid.

Constantius also regained the allegiance of the rebellious Gallic legion and defeated the Franks of the Rhine mouth who seem to have been working in league with Carausius. Weakened by these setbacks, Carausius was assassinated by his treasurer, Allectus.

In legend

In his mediaeval history, Geoffrey of Monmouth wrote that Carausius was given the kingship of the Britons over that of Caracalla, who died many years earlier. At some point in time, Carausius was able to sway the Picts to join him and they turned on the Romans. Caracalla was forced to flee Britain and it remained in Carausius's control for some time. He gave the Picts large tracts of land in Albany where they settled and married Britons.

External link

• http://www.romanbritain.freeserve.co.uk/CARAUSIUS.HTM