History of the Peloponnesian War

Meanwhile the opponents of the traitors, being numerous enough to prevent the gates being opened to him at once, acting in concert with Eucles the general, who had come from Athens as warden of the place, sent to the other commander of the Thracian district, Thucydides son of Olorus, the author of this history, who was at Thasos, a Parian colony, about a half-day's sail from Amphipolis, and urged him to come to their aid.

And he, on hearing this, sailed in haste with seven ships which happened to be at hand, wishing above all to secure Amphipolis before it yielded, or, failing in that, to seize Eion.

Meanwhile, Brasidas, fearing the arrival of the ships from Thasos, and hearing that Thucydides possessed the right of working the gold-mines in that part of Thrace and in consequence had influence among the first men of the mainland, made haste to seize the city if possible before he should come; for he was afraid that, if Thucydides should arrive, the popular party in Amphipolis, in the expectation that he would collect an allied force from the islands and from Thrace and relieve them, would refuse to yield.

Accordingly, he offered moderate terms, making proclamation to this effect, that any citizen of Amphipolis or any resident Athenian, if he chose, might remain there, retaining possession of his own property and enjoying full equality; but that anyone who was not inclined to stay might go away within five days and take his property with him.