History of the Peloponnesian War
Thucydides
Thucydides. The history of the Peloponnesian War, Volume 1-2. Dale, Henry, translator. London: Heinemann and Henry G. Bohn, 1851-1852.
Now the day before this battle it also happened that the Epidaurians with all their forces invaded the Argive territory, and cut off in great numbers, when they came out to give them battle, those of the Argives who were left behind to keep
guard. Moreover, when three thousand of the Elean heavy-armed had come after the battle to the succour of the Mantineans, and a thousand Athenians in addition to their former force, all these allies at once marched against Epidaurus, while the Lacedaemonians were keeping the Carnea; and dividing the work between them, they began a wall of circumvallation round the
city. And though the rest abandoned the work, the Athenians finished it round the promontory called the Heraeum, the part which had been assigned to them. And having all joined in leaving a garrison in this fortress, they returned to their several cities. And so the summer ended.
At the beginning of the following winter, the Lacedaemonians, after they had celebrated the Carnean festival, immediately took the field; and on arriving at Tegea, sent on to Argos proposals for an accommodation.
For there had been there previously a party in their interest, and desirous of putting down the democracy at Argos; and since the battle had been fought, they were much better able to persuade the people at large to the proposed arrangement. Their wish was, after first concluding a treaty with the Lacedaemonians, then, in the second place, to enter into alliance with them; and so at length to attack the democracy.