C. Julius Caesar, Gallic War

It is again told Caesar, that the Helvetii intended to march through the country of the Sequani and the Aedui into the territories of the Santones, which are not far distant from those boundaries of the Tolosates, which [viz. Tolosa , Toulouse] is a state in the Province. If this took place, he saw that it would be attended with great danger to the Province to have warlike men, enemies of the Roman people, bordering upon an open and very fertile tract of country. For these reasons he appointed Titus Labienus, his lieutenant, to the command of the fortification which he had made. He himself proceeds to Italy by forced marches, and there levies two legions, and leads out from winter-quarters three which were wintering around Aquileia , and with these five legions marches rapidly by the nearest route across the Alps into Further Gaul. Here the Centrones and the Graioceli and the Caturiges, having taken possession of the higher parts, attempt to obstruct the army in their march. After having routed these in several battles, he arrives in the territories of the Vocontii in the Further Province on the seventh day from Ocelum, which is the most remote town of the Hither Province; thence he leads his army into the country of the Allobroges, and from the Allobroges to the Segusiani. These people are the first beyond the Province on the opposite side of the Rhone .