Carausius in Wikipedia

Marcus Aurelius Mausaeus Valerius Carausius (died 293) was a military commander of the Roman Empire in the 3rd century. He was a Menapian from Belgic Gaul, who usurped power in 286, declaring himself emperor in Britain and northern Gaul. He did this only 13 years after the Gallic Empire of the Batavian Postumus was ended in 273. He held power for seven years, before being assassinated by his finance minister Allectus (see Carausian Revolt). Carausius was a man of humble origin, a Menapian who distinguished himself during Maximian's campaign against the Bagaudae rebels in northern Gaul in 286. This success, and his former occupation as a pilot, led to his appointment to command the Classis Britannica, a fleet based in the English Channel, with the responsibility of eliminating Frankish and Saxon pirates who had been raiding the coasts of Armorica and Belgica. However, he was suspected of keeping captured treasure for himself, and even of allowing the pirates to carry out raids and enrich themselves before taking action against them, and Maximian ordered his execution. In late 286 or early 287 Carausius learned of this sentence and responded by declaring himself Emperor in Britain and northern Gaul.[1] His forces comprised not only his fleet, augmented by new ships he had built, and the three legions stationed in Britain, but a legion he had seized in Gaul, a number of foreign auxiliary units, a levy of Gaulish merchant ships, and barbarian mercenaries attracted by the prospect of booty...

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