History of the Peloponnesian War

Indeed at Samos the question of the oligarchy had already entered upon a new phase, the following events having taken place just at the time that the Four Hundred were conspiring.

That part of the Samian population which has been mentioned as rising against the upper class, and as being the democratic party, had now turned round, and yielding to the solicitations of Pisander during his visit, and of the Athenians in the conspiracy at Samos, had bound themselves by oaths to the number of three hundred, and were about to fall upon the rest of their fellow-citizens, whom they now in their turn regarded as the democratic party.

Meanwhile they put to death one Hyperbolus, an Athenian, a pestilent fellow that had been ostracised, not from fear of his influence on position, but because he was a rascal and a disgrace to the city; being aided in this by Charminus, one of the generals, and by some of the Athenians with them, to whom they had sworn friendship, and with whom they perpetrated other acts of the kind, and now determined to attack the people.