The country north of the Matrona and Sequana was inhabited by the BELGAE, who belonged to the race of the Cymri, and were mixed with Germans only accidentally, because conquered Germans lived among them. The _Remi_, with their capital of _Durocortorum_, were the most distinguished tribe among them in the time of Caesar, and they continued to be great for a long time after, although during the Roman wars they had, properly speaking, fallen from their height. The frontier between the Belgae and Germany is involved in much obscurity; in regard to many tribes, such as the Menapii, it is even doubtful as to whether they were Germans or Cymri. The _Treviri_, according to Tacitus, were _ambitiosi circa Germanicam originem_. On the whole, it would seem that eighteen or nineteen hundred years ago the frontier of the Germans was pretty much the same as it is now. Alsace was occupied by Germans, and the Vosges mountains, and the modern Walloon district about Liege probably formed the boundary. It is possible that at a later period Brabant and Flanders were still Cymric, but nothing decisive can be said about this.[73] The German nations were divided, in the Roman administration into two great parts, _Germania prima_ and _secunda_, which were connected with Gaul only on account of the general government, but were not included by the Romans in the name of Gaul; and at a later time, they were politically separated, because they were under a military government. Treves was the capital of these parts; in Tacitus it is still called TREVIRI, but afterwards AUGUSTA TREVIRORUM. Ever since the third century, it was probably a considerable city, though not in its circumference, which people generally are inclined to make much too large; it does not appear to have been much greater than that of its present walls, which, however, is not inconsiderable, if the place was well peopled. The amphitheatre was no doubt outside the walls, as in all Roman towns, except Rome itself. The greatness of Treves extends from the middle of the third to the fifth century; the architectural remains, as is evident from their style, belong to that period. It is the period after Maximinus, or somewhat later, after Valerian, when the barbarians advanced on all sides; the Gallic emperors resided at Treves. COLONIA AGRIPPINA (Cologne) was less important; it was a frontier fortress and a prosperous colony; but by no means of the importance of Treves.