History of the Peloponnesian War

Afterwards Brasidas let the allies go home, and himself went back to Corinth, to prepare for his expedition to Thrace, his original destination.

The Athenians also returning home, the Megarians in the city most implicated in the Athenian negotiation, knowing that they had been detected, presently disappeared; while the rest conferred with the friends of the exiles, and restored the party at Pegae, after binding them under solemn oaths to take no vengeance for the past, and only to consult the real interests of the town.

However, as soon as they were in office, they held a review of the heavy infantry, and separating the battalions, picked out about a hundred of their enemies, and of those who were thought to be most involved in the correspondence with the Athenians, brought them before the people, and compelling the vote to be given openly, had them condemned and executed, and established a close oligarchy in the town—

a revolution which lasted a very long while, although effected by a very few partisans.