Titus Livius (Livy), The History of Rome, Book 23
Frank Gardener Moore, Professor Emeritus in Columbia University, Ed.

24. On the next day the senate, presided over by Marcus Pomponius, the praetor, decreed that the dictator should be informed by letter that, if he thought it to the public interest, he should come with the master of the horse and the praetor, Marcus Marcellus, for the election of consuls, in [2??] order that from them in person the fathers could learn what was the condition of the state and make their plans in accordance with the facts. All of those summoned came, leaving their lieutenants to command the legions. [3] The dictator spoke briefly and [p. 81]modestly of himself, and then diverted a large share¹ of the glory² to the master of the horse, Tiberius Sempronius Gracchus; and he ordered the elections at which these consuls were named: Lucius Postumius for the third time, then absent with Gaul as his sphere of action, and Tiberius Sempronius Gracchus, who was at that time master of the horse and curule aedile. [4] Then the following men were elected as praetors: Marcus Valerius Laevinus for the second time, Appius Claudius Pulcher, Quintus Fulvius Flaccus, Quintus Mucius Scaevola. [5] The dictator, after the election of magistrates, returned to the army and the winter quarters at Teanum,³ leaving the master of the horse at Rome, in order that he, inasmuch as he was to enter upon office a few days later, might advise with the fathers in regard to enrolling and providing armies for the year.

[6] Just as these measures were being taken, a fresh disaster was reported —for fortune was piling one upon another for that year —namely, that the consul designate, Lucius Postumius, had perished, himself and his army, in Gaul. There was a huge forest,⁴ called Litana by the Gauls, by way of which he was about to lead his army. [7] In that forest the Gauls hacked the trees to right and left of the road in such a way that, if not disturbed, they stood, but fell if pushed slightly. [8] Postumius had two Roman legions, and had enlisted from the coast of the Upper Sea⁵ such numbers of allies that he led twenty-five thousand armed men into the enemy's territory. [9] The Gauls had surrounded the very edge of the forest, [p. 83]and when the column entered a defile⁶ they pushed⁷ against the outermost of the trees that had been hacked near the ground. As these fell, each upon the next tree, which was in itself unsteady and had only a slight hold, piling up from both sides they overwhelmed arms, men and horses, so that hardly ten men escaped. [10] For after very many had been killed by tree-trunks and broken branches, and the rest of the troops were alarmed by the unforeseen calamity, the Gauls under arms, surrounding the whole defile⁸ slew them, while but few out of so many were captured, —the men who were making their way to a bridge over a river, but were cut off, since the bridge had by that time been occupied by the enemy. [11] There Postumius fell fighting with all his might to avoid capture. Spoils taken from his body and the severed head of the general were carried in triumph by the Boians to the temple which is most revered in their land. [12] Then after cleaning the head they adorned the skull with gold according to their custom. And it served them as a sacred vessel from which to pour libations at festivals and at the same time as a drinking cup for the priests and keepers of the temple. [13] The booty also meant no less to the Gauls than the victory. For although a large part of the cattle had been crushed by fallen trees, still everything else was found strewn the whole length of the column of the slain, since nothing was scattered by flight.