There can be no greater error than to suppose that the withdrawal of the Roman legions from Britain in 407, and the rescript of the Emperor Honorius, three or four years later, permitting the citizens of Britain to arm themselves and provide for their own defence, meant the instant departure of all things Roman from British shores, the death of Roman traditions, the end of Roman civilisation. The idea that the island almost immediately relapsed into something resembling its pre-Roman condition is due partly to the scanty nature of our evidence, partly to a misreading of the famous work of Gildas “on the decline and fall of Britain,” partly to a mistaken idea of the isolation of Britain from the continent, and largely to that anachronistic habit, into which it is so easy to fall, of judging men’s acts and thoughts as if they could have foreseen the future. It cannot be too strongly enforced that in those years which mark _for us_ the Roman surrender of Britain, and for many years after, no man—emperor or imperial minister or British provincial—could have thought or realised that the events which they were witnessing meant a final dismemberment of the Empire in the west, that Britain was really cut off for ever. The Empire had weathered storms before, and emerged stable and strong; to the contemporaries of Honorius and Valentinian the Empire was part of the established order of things, and a suspension of its control in any particular portion of its dominion was something temporary and passing. The British provincials did not and could not for a moment regard themselves and their province as finally severed from Rome; they still considered themselves part of the Empire; for a hundred and fifty years some of them at least considered themselves Roman citizens. From this point of view alone it is not conceivable that the traditions and machinery of the Roman administration should have disappeared at once, the moment the central authorities ceased to control it. What could the provincials have deliberately put in its place? All the circumstances seem to enforce the conclusion that the administration, in its general lines, continued, but was gradually modified, and ultimately decayed, through three main causes—financial necessities which must have soon led to a reduction of the elaborate machinery of administration, the organisation of new methods of self-help, and the development of local interests promoted by the ambition of private persons who won power and supremacy in various districts. There was doubtless a Celtic revival, but for many years after the rescript of Honorius, Roman institutions must have continued to exist alongside of, or controlled by, the local potentates, who are described as “kings” or “tyrants.” And in the later years of the fifth century the great successes won by the British against the English invaders were achieved by generals—Ambrosius Aurelianus, and Arthur—who were not