These invaders were succeeded by a second wave of Celtic-speaking peoples, the Cymry or Brythons, who drove their Goidelic predecessors still farther westward and exterminated and absorbed them over large areas. These Cymric invasions occurred about 300–100 B. C. and were probably the result of the growing development of the Teutons and their final expulsion of the Celtic-speaking tribes from Germany. These Cymry occupied northern France under the name of Belgæ and invaded England as Brythons in several waves, the last being the true Belgæ. The conquests of these Cymric tribes in both Gaul and Britain were only checked by the legions of Rome. These migrations are exceedingly hard to trace because of the confusion caused by the fact that Celtic speech is now found on the lips of populations in nowise related to the Nordics who first introduced it. But one fact stands out clearly, all the original Celtic-speaking tribes were Nordic. What were the special physical characters of these tribes in which they differed from their Teutonic successors is now impossible to say, beyond the possible suggestion that in the British Isles the Scottish and Irish populations in which red hair and gray or green eyes are abundant have rather more of this Celtic strain in them than have the flaxen haired Teutons, whose china-blue eyes are clearly not Celtic. When the peoples called Gauls or Celts by the Romans and Galatians by the Greeks first appear in history they are described in exactly the same terms as were later the Teutons. They were all gigantic barbarians with fair and very often red hair, then more frequent than to-day, with gray or fiercely blue eyes and were thus clearly members of the Nordic subspecies. The first Celtic-speaking nations with whom the Romans came in contact were Gaulish and had probably incorporated much Alpine blood by the time they crossed the mountains into the domain of classic history. The Nordic element had become still weaker by absorption from the conquered populations when at a later date the Romans broke through the ring of Celtic nations and came into contact with the Nordic Cymry and Teutons. After these early expansions of Gauls and Cymry the Teutons appear upon the scene. Of the pure Teutons within the ken of history, it is not necessary to mention more than the most important of the long series of conquering tribes.