They were severely chastised by Theodosius, who visited Britain in 343. He succeeded in expelling them from the Roman provinces and driving them back to their wild retreats.
Maximus, who afterwards assumed the title of Augustus, while in Britain, carried on the war against the Picts and Scots with unrelenting severity; his ambition, however, led him to attempt the conquest of the whole western empire, in which he failed, and was beheaded at Aquileia. His army, comprising a large majority of Britons, never returned to their native country, which consequently was left in a great measure defenceless. So favourable an opportunity did not escape the vigilance of the Picts and Scots, who made successive inroads in the island, and returned to their mountain fastnesses laden with plunder.
The power of Rome was now shaken by the irruption of barbarians of various denominations, who, issuing from the east and north, depopulated her fairest provinces. Assailed at so many points at once, it seemed as if the nations of the earth had been let loose to uproot her supremacy, and break the shackles which for so many ages had fettered the greater part of the world. The Goths, led by Alaric, crossing the Julian Alps, swept like a torrent over the fertile plains of Italy. Other German tribes devastated Gaul, and the Roman legions in Britain, deprived of all communication with the Emperor Honorius, fell back upon their custom of electing an emperor for themselves.
The first whom they selected for the purple was Marcus, whom his soldiers, very soon after elevating him to the imperial dignity, put to death; after him came an adventurer named Constantine, who paid for his short-lived dignity with his life. A third usurper arose in Gerontius.
[Illustration: ROMAN SOLDIERS LEAVING BRITAIN. (_See p._ 18.)]
When the Emperor Honorius heard of this revolution, he wrote to the states of Britain, to say that they must provide for their safety, and govern themselves; by which concession the rule of Rome in the island was looked on as at an end. The Britons, in despair, rose and drove out their civil governors. About 367 years after the landing of Plautius, the evacuation of Britain was complete. No doubt to a large number of the Imperial soldiers this withdrawal meant the severance of many tender ties, and some of the leave-takings must have been painful enough.