Strabo Geography 4.1.1

[1] NEXT in order [after Iberia] comes Keltica beyond the Alps, ¹ the configuration and size of which has been already mentioned in a general manner; we are now to describe it more particularly. Some divide it into the three nations of the Aquitani, Belge, and Kelte. ² Of these the Aquitani differ completely from the other nations, not only in their language but in their figure, which resembles more that of the Iberians than the Galatae. The others are Galatae in countenance, although they do not all speak the same language, but some make a slight difference in their speech; neither is their polity and mode of life exactly the same. These writers give the name of Aquitani and Keltae to the dwellers near the Pyrenees, which are bounded by the Cevennes. For it has been stated that this Keltica is bounded on the west by the mountains of the Pyrenees, which extend to either sea, both the Mediterranean and the ocean; on the east by the Rhine, which is parallel to the Pyrenees; on the north by the ocean, from the northern extremities of the Pyrenees to the mouths of the Rhine; on the south by the sea of Marseilles, and Narbonne, and by the Alps from Liguria to the sources of the Rhine. The Cevennes lie at right angles to the Pyrenees, and traverse the plains for about 2000 stadia, terminating in the middle near Lugdunum. ³ They call those people Aquitani who inhabit the northern portions of the Pyrenees, and the Cevennes extending as far as the ocean, and bounded by the river Garonne; and Keltae, those who dwell on the other side of the Garonne, towards the sea of Marseilles and Narbonne, and touching a portion of the Alpine chain. This is the division adopted by divus Caesar in his Commentaries. ⁴ But Augustus Caesar, when dividing the country into four parts, united the Keltae to the Narbonnaise; the Aquitani he preserved the same as Julius Caesar, but added thereto fourteen other nations of those who dwelt between the Garonne and the river Loire, ⁵ and dividing the rest into two parts, the one extending to the upper districts of the Rhine he made dependent upon Lugdunum, the other [he assigned] to the Belgae. However, it is the duty of the Geographer to describe the physical divisions of each country, and those which result from diversity of nations, when they seem worthy of notice; as to the limits which princes, induced by a policy which circumstances dictate, have variously imposed, it will be sufficient for him to notice them summarily, leaving others to furnish particular details.