Meanwhile, Brasidas succeeded in persuading Acanthus to revolt, he himself winning the highest of reputations for justice and moderation as well as for military skill.  Later in the year he suddenly turned his forces against the Athenian colony of Amphipolis, which he induced to surrender by offering very favourable terms before Thucydides, who was in command of Thasos, arrived to relieve it.  The further successes of Brasidas during this winter made the Athenians ready to treat for peace, and a truce was agreed upon for twelve months.  Brasidas, however, continued to render aid to the subject cities which revolted from Athens—­this being now the ninth year of the war—­but he failed in an attempt to capture Potidaea.

The period of truce terminating without any definite peace being arrived at, the summer of the tenth year is chiefly notable for the expedition sent under Cleon to recover Amphipolis, and for a recrudescence of the old quarrel in Sicily between Leontini and Syracuse.  Before Amphipolis, the incompetent Cleon was routed by the skill of Brasidas; but the victor as well as the vanquished was slain, though he lived long enough to know of the victory.  Their deaths removed two of the most zealous opponents of the peace for which both sides were now anxious.  Hence at the close of the tenth year a definite peace was concluded.

The Lacedaemonians, however, were almost alone in being fully satisfied by the terms, and the war was really continued by an anti-Laconian confederation of the former Peloponnesian allies, who saw in the peace a means to the excessive preponderance of Athens and Sparta.  Argos was brought into the new confederacy in the hope of establishing her nominal equality with Sparta.  For some years from this point the combinations of the states were constantly changing, while Athens and Sparta remained generally on terms of friendliness, the two prominent figures at Athens being the conservative Nicias and the restless and ambitious young intriguer Alcibiades.

In the fourteenth year there were active hostilities between Argos, with which by this time Athens was in alliance, and Lacedaemon, issuing in the great battle of Mantinea, where there was an Athenian contingent with the Argives.  This was notable especially as completely restoring the prestige of the Lacedaemonian arms, their victory being decisive.  The result was a new treaty between Sparta and Argos, and the dissolution of the Argive-Athenian alliance; but this was once more reversed in the following year, when the Argive oligarchy was attacked successfully by the popular party.

The next year is marked by the high-handed treatment of the island of Melos by the Athenians.  This was one of the very few islands which had not been compelled to submit to Athens, but had endeavoured to remain neutral.  Thither the Athenians now sent an expedition, absolutely without excuse, to compel their submission.