Next year, the Athenians dispatched a larger fleet with Sicily for its objective.  Demosthenes, however, who had a project of his own in view, was given an independent command.  He was thus enabled to seize and fortify Pylos, a position on the south-west of Peloponnese, with a harbour sheltered by the isle of Sphacteria.  The Spartans, in alarm, withdrew their invading force from Attica, and attempted to recover Pylos, landing over 400 of their best men on Sphacteria.  The locality now became the scene of a desperate struggle, which finally resulted in the Spartans on Sphacteria being completely isolated.

So seriously did the Lacedaemonians regard this blow that they invited the Athenians to make peace virtually in terms of an equal alliance; but the Athenians were now so confident of a triumphant issue that they refused the terms—­chiefly at the instigation of Cleon.  Some supplies, however, were got into Sphacteria, owing to the high rewards offered by the Lacedaemonians for successful blockade-running.  At this moment, Cleon, the Athenian demagogue, having rashly declared that he could easily capture Sphacteria, was taken at his word and sent to do it.  He had the wit, however, to choose Demosthenes for his colleague, and to take precisely the kind of troops Demosthenes wanted; with the result that within twenty days, as he had promised, the Spartans found themselves with no other alternatives than annihilation or surrender.  Their choice of the latter was an overwhelming blow to Lacedaemonian prestige.

III.—­Victories of Lacedaemon

The capture of the island of Cythera in the next summer gave the Athenians a second strong station from which they could constantly menace the Peloponnese.  On the other hand, in this year the Sicilians were awakening to the fact that Athens was not playing a disinterested part on behalf of the Ionian states, but was dreaming of a Sicilian empire.  At a sort of peace congress, Hermocrates of Syracuse successfully urged all Sicilians to compose their quarrels on the basis of uti possidetis, and thus deprive the Athenians of any excuse for remaining.  Thus for the time Athenian aspirations in that quarter were checked.

At Megara this year the dissensions of the oligarchical and popular factions almost resulted in its capture by the Athenians.  The Lacedaemonian Brasidas, however—­who had distinguished himself at Pylos—­effected an entry, so that the oligarchical and Peloponnesian party became permanently established in power.  The most important operations were now in two fields.  Brasidas made a dash through Thessaly into Macedonia, in alliance with Perdiccas of Macedon, with the hope of stirring the cities of Chalcidice to throw off the Athenian yoke; and the democrats of Boeotia intrigued with Athens to assist in a general revolution.  Owing partly to misunderstandings and partly to treachery, the Boeotian democrats failed to carry out their programme, the Athenians were defeated at Delium, and Delium itself was captured by the Boeotians.