(at York), one Artorius Justus, was sent with a part of the British garrison to reduce it to obedience.[1] It may therefore have been, as Mommsen suggests, one of the least Romanized corners of Gaul, and in it the native idiom may have retained unusual vitality.  Yet that native speech was not strong enough to live on permanently.  The Celtic which is spoken to-day in Brittany is not a Gaulish but a British Celtic; it is the result of British influences.  Brittany would have sooner or later become assimilated to the general Romano-Gaulish civilization, had not its Celtic elements won fresh strength from immigrant Britons.  This immigration is usually described as an influx of refugees fleeing from Britain before the English advance.  That, no doubt, was one side of it.  But the principal immigrants, so far as we know their names, came from Devon and Cornwall,[2] and some certainly did not come as fugitives.  The King Riotamus who (as Jordanes tells us) brought 12,000 Britons in A.D. 470 to aid the Roman cause in Gaul, was plainly not seeking shelter from the English.[3] We must connect him, and indeed the whole fifth-century movement of Britons into Gaul, with the Celtic revival and with the same causes that produced for instance, the Scotic invasion of Caledonia.

[Footnote 1:  C. iii. 1919=Dessau 2770.  The inscription must be later than (about) A.D. 200, and it somewhat resembles another inscription (C. iii. 3228) of the reign of Gallienus, which mentions milites vexill. leg.  Germanicar. et Britannicin. cum auxiliis earum.  Presumably it is either earlier than the Gallic Empire of 258-73, or falls between that and the revolt of Carausius in 287.  The notion of O. Fiebiger (De classium Italicarum historia, in Leipziger Studien, xv. 304) that it belongs to the Aremoric revolts of the fifth century is, I think, wrong.  Such an expedition from Britain at such a date is incredible.]

[Footnote 2:  The attempt to find eastern British names in Brittany seems a failure.  M. de la Borderie, for instance, thinks that Corisopitum (or whatever the exact form of the name is) was colonized from Corstopitum (Corbridge on the Tyne, near Hadrian’s Wall).  But the latter, always to some extent a military site, can hardly have sent out ordinary emigres, while the former has hardly an historical existence at all, and may be an ancient error for civitas Coriosolitum (C. xiii (I), i. p. 491).]

[Footnote 3:  Freeman (Western Europe in the Fifth Century, p. 164) suggests that a migration of Britons into Gaul had been in progress, perhaps since the days of Magnus Maximus, and that by 470 there was a regular British state on the Loire, from which Riotamus led his 12,000 men.  Hodgkin (Cornwall and Brittany, Penryn, 1911) suggests that the soldiers of Maximus settled on the Loire about 388, and that Riotamus was one of their descendants.  He quotes Gildas as saying that the British troops of Maximus went abroad with him and never returned.  That, however, is an entirely different thing from saying that they settled in a definite part of Gaul.  For this latter statement I can find no evidence, and the Celtic revival in our island seems to provide a better setting for the whole incident of Riotamus.