History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
On the other hand, the Ambraciots and those on the enemy's right wing defeated the troops opposed to themselves, and pursued them to Argos; and indeed these are the best fighters of all the peoples of that region.
When, however, they returned and saw that their main army had been defeated, and the victorious division of the Acarnanians began to press hard upon them, they made their escape with difficulty to Olpae; and many of them were killed, for they rushed on with broken ranks and in disorder all except the Mantineans, who kept their ranks together during the retreat better than any other part of the army. And it was late in the evening before the battle ended.
On the next day, since Eurylochus and Macarius had been slain, Menedaius had on his own responsibility assumed the command, but the defeat had been so serious that he was at his wit's end how, if he remained, he could stand a siege, blockaded as he was by both land and sea by the Athenian fleet, or, if he retreated, could get away safely. He therefore made overtures to Demosthenes and the Athenian generals regarding a truce for his retreat and also about the recovery of his dead.
And they gave back the dead, set up a trophy themselves, and took up their own dead, about three hundred in number. They would not, however, openly agree to a retreat for the whole army, but Demosthenes with his Acarnanian colleagues secretly agreed that the Mantineans and Menedaius and the other Peloponnesian commanders and the most influential men among them might go back home, if they did so speedily. Their object was to isolate the Ambraciots and the miscellaneous crowd of mercenaries,[*](Opinions differ as to who are meant. They were probably mercenaries from the neighbouring Epirote tribes in the pay of the Ambraciots.) and above all to discredit the Lacedaemonians and the Peloponnesians with the Hellenes of this region, on the ground that they had committed an act of treachery through preference for their own selfish interests.