In 56 BC, the Sotiates were led by their chief Adiatuanos in the defence of their oppidum against the Roman officer P. Licinius Crassus. After a failed sortie attempt with 600 of his soldurii, Adiatuanos had to capitulate to the Romans.
Cassius then marched his army into the borders of the Sotiates. Hearing of his approach, the Sotiates collected a large force, with cavalry, in which lay their chief strength, and attacked our column on the march. First of all they engaged in a cavalry combat; then, when their cavalry were beaten, and ours pursued, they suddenly unmasked their infantry force, which they had posted in ambush in a valley. The infantry attacked our scattered horsemen and renewed the fight.
The battle was long and fierce. The Sotiates, with the confidence of previous victories, felt that upon their own courage depended the safety of all Aquitania: the Romans were eager to have it seen what they could accomplish under a young leader without the commander-in-chief and the rest of the legions. At last, however, after heavy casualties the enemy fled from the field. A large number of them were slain; and then Crassus turned direct from his march and began to attack the stronghold of the Sotiates. When they offered a brave resistance he brought up mantlets and towers.
The enemy at one time attempted a sortie, at another pushed mines as far as the ramp and the mantlets—and in mining the Aquitani are by far the most experienced of men, because in many localities among them there are copper-mines and diggings. When they perceived that by reason of the efficiency of our troops no advantage was to be gained by these expedients, they sent deputies to Crassus and besought him to accept their surrender.
Their request was granted, and they proceeded to deliver up their arms as ordered. Then, while the attention of all our troops was engaged upon that business, Adiatunnus, the commander-in-chief, took action from another quarter of the town with six hundred devotees, whom they call vassals. The rule of these men is that in life they enjoy all benefits with the comrades to whose friendship they have committed themselves, while if any violent fate befalls their fellows, they either endure the same misfortune along with them or take their own lives; and no one yet in the memory of man has been found to refuse death, after the slaughter of the comrade to whose friendship he had devoted himself. With these men Adiatunnus tried to make a sortie; but a shout was raised on that side of the entrenchment, the troops ran to arms, and a sharp engagement was fought there. Adiatunnus was driven back into the town; but, for all that, he begged and obtained from Crassus the same terms of surrender as at first.
— Julius Caesar. Bellum Gallicum. 3, 20–22. Loeb Classical Library. Translated by H. J. Edwards, 1917.