CARAUSIUS, MARCUS AURELIUS, tyrant or usurper in Britain, A.D. 286-293, was a Menapian from Belgic Gaul, a man of humble origin. In the Roman army he rapidly obtained promotion and was stationed by the emperor Maximian at Gessoriacum (Bononia, Boulogne) to ward off Frankish and Saxon pirates. On being accused of partnership with the barbar ians he was sentenced to death by the emperor, but he escaped to Britain and proclaimed himself an independent ruler. In 289 Maximian attempted to recover the island, but his fleet was damaged by a storm and he was compelled to acknowledge the rule of Carausius in Britain. Numerous coins are extant bearing the heads of Carausius, Diocletian and Maximian, and the legend "Carausius et fratres sui." In 292 Constantius Chlorus captured Gessoriacum (hitherto in possession of Carausius) and then made preparations to reconquer Britain, but before they were completed Carausius was murdered by Allectus, his praefect of the guards (Aurelius Victor, Caesares, 39; Eutropius ix. 21, 22 ; Eumenius, Panegyrici ii. 12, V. I 2) .
See J. Watts de Peyster, The History of Carausius, the Dutch Augustus (i858) ; P. H. Webb, The Reign and Coinage of Carausius (1908).