Plutarch, Caesar
Bernadotte Perrin, Ed.

26. This leader, then, after dividing his forces into many parts and putting many officers in command of them, was winning over all the country round about as far as the water-shed of the Arar. He purposed, now that there was a coalition at Rome against Caesar, at once to rouse all Gaul to war. If he had done this a little later, when Caesar was involved in the civil war, Italy would have been a prey to terrors no less acute than those aroused by the Cimbri of old. [2] But as it was, the man endowed by nature to make the best use of all the arts of war, and particularly of its crucial moments, namely Caesar, as soon as he learned of the revolt, set out and marched by the same roads over which he had previously come, and by the vigour and speed of his passage in so severe a winter showed the Barbarians that an unconquered and invincible army was coming against them. For where it was incredible that one of his messengers or letter-carriers could make his way in a long time, there he was seen with his whole army, at once ravaging their lands and destroying their strongholds, subduing cities, [3] and receiving those who came over to his side, until the nation of the Aedui also entered the war against him. These up to this time had called themselves brethren of the Romans and had been conspicuously honoured, but now, by joining the rebels, they caused great dejection in Caesar's army. In consequence of this Caesar removed from those parts and passed across the territory of the Lingones, wishing to reach the country of the Sequani, who were friends, and stood as a bulwark between Italy and the rest of Gaul. [4] There the enemy fell upon him and surrounded him with many tens of thousands, so that he essayed to fight a decisive battle. In the main he got the best of the struggle, and after a long time and much slaughter overpowered the Barbarians; but it appears that at first he met with some reverse, and the Arverni show a short-sword hanging in a temple, which they say was captured from Caesar. When Caesar himself saw it, at a later time, he smiled, and though his friends urged him to have it taken down, he would not permit it, considering it sacred.