In the next—­the fifth—­summer, Mitylene capitulated; the fate of the inhabitants was to be referred to Athens.  Here Cleon had now become the popular leader, and he persuaded the Athenians to order the whole of the adult males to be put to death.  The opposition, however, succeeded in getting this bloodthirsty resolution rescinded.  The second dispatch, racing desperately after the first, did not succeed in overtaking it, but was just in time to prevent the order for the massacre from being carried out.  Lesbos was divided among Athenian citizens, who left the Lesbians in occupation as before, but drew a large rental from them.

In the same summer the remaining garrison of Plataea surrendered to the Lacedaemonians, on terms to be decided by Lacedaemonian commissioners.  Before them the Plataeans justified their resistance, but the commissioners ignored the defence, and, on the pretext that the only question was whether they had suffered any “wrong” at the hands of the Plataeans, and that the answer to that was obvious, put the Plataeans to death and razed the city to the ground.

Meanwhile, at Corcyra, the popular and the oligarchical parties, who favoured the Athenians and Peloponnesians respectively, had reached the stage of murderous hostility to each other.  The oligarchs captured the government, and were then in turn attacked by the popular party; and there was savage faction fighting.  An attempt was made by the commander of the Athenian squadron at Naupactus to act as moderator; the appearance of a Peloponnesian squadron and a confused sea-fight, somewhat in favour of the latter, brought the popular party to the verge of a compromise.  But the Peloponnesians retired on the reported approach of a fresh Athenian fleet, and a democratic reign of terror followed.

“The father slew the son, and the supplicants were torn from the temples and slain near them.”  And thus was initiated the peculiar horror of this war—­the desperate civil strife in one city after another, oligarchs hoping to triumph by Lacedaemonian and democrats by Athenian, support, and either party, when uppermost, ruling by terror.  It was at this time also that the Ionian and Dorian cities of Sicily, headed by Leontini and Syracuse respectively, went to war with each other, and an Athenian squadron was first induced to participate in the struggle.

Among the operations of the next, or sixth, summer was a campaign which the Athenian commander Demosthenes conducted in AEtolia—­successful at the outset, but terminating in disaster, which made the general afraid to return to Athens.  He seized a chance, however, of recovering his credit by foiling a Lacedaemonian expedition against Naupactus; and in other ways he successfully established a high military reputation, so that he was no longer afraid to reappear at Athens.