Carausian revolt
In 286 Diocletian appointed his deputy Maximian as co-emperor to rule the West while he himself ruled the East. Almost immediately the Germanic tribes invaded Gaul while Frankish and Saxon pirates raided the Channel. To deal with the pirates, Maximian placed the general Carausius in charge of the Channel fleet, but, after being accused of corruption, Carausius fled to Britain with the fleet and proclaimed himself emperor.[1]
The Britannic Empire was a short-lived breakaway state of the Roman empire in the late Roman Period. Formed as a result of the revolt by the naval commander Carausius. It ended when Carausius's usurper, Allectus, was defeated by the Emperor Constantius I in 296.