12.] Their retreat brought on a new invasion of the enemy.

The Britons made again an application to Rome, and again obtained the assistance of a legion, which proved effectual for their relief: but the Romans, reduced to extremities at home, and fatigued with those distant expeditions, informed the Britons that they must no longer look to them for succor, exhorted them to arm in their own defence, and urged, that, as they were now their own masters, it became them to protect by their valor that independence which their ancient lords had conferred upon them.[*] That they might leave the island with the better grace, the Romans assisted them in erecting anew the wall of Severus, which was built entirely of stone, and which the Britons had not at that time artificers skilful enough to repair.[*] [* Paul.Diacon.p.

43.] And having done this last good office to the inhabitants, they bade a final adieu to Britain, about the year 448, after being masters of the more considerable part of it during the course of near four centuries.
THE BRITONS.
The abject Britons regarded this present of liberty as fatal to them; and were in no condition to put in practice the prudent counsel given them by the Romans, to arm in their own defence.

Unaccustomed both to the perils of war and to the cares of civil government, they found themselves incapable of forming or executing any measures for resisting the incursions of the barbarians.

Gratian also and Constantine, two Romans who had a little before assumed the purple in Britain, had carried over to the continent the flower of the British youth; and having perished in their unsuccessful attempts on the imperial throne, had despoiled the island of those who, in this desperate extremity, were best able to defend it.