After the death of Pericles, the war was continued, without interruption, for seven years longer, but with no very decisive advantage to either side. During this period the Athenian councils were chiefly directed by a coarse-minded and unprincipled demagogue named Cleon, who was at last killed in battle under the walls of Amphipolis, a Macedonian city, of which the possession was disputed by the Athenians and Lacedæmonians. Cleon was succeeded in the direction of public affairs by Nicias, the leader of the aristocratic party, a man of virtuous but unenterprising character, and a military officer of moderate abilities. Under his auspices a peace for fifty years, commonly known by the name of the ‘Peace of Nicias,’ was concluded in the tenth year of the war (421 B. C.). It was not long, however, till the contest was resumed. Offended that its allies had given up a contest undertaken for the assertion of its alleged rights, Corinth refused to be a party to the treaty of peace, and entered into a new quadruple alliance with Argos, Elis, and Mantinæa, a city of Arcadia; the ostensible object of which confederation was the defense of the Peloponnesian states against the aggressions of Athens and Sparta. This end seemed not difficult of attainment, as fresh distrust had arisen between the two last-mentioned republics, on account of the reluctance felt and manifested by both to give up certain places which they had bound themselves by treaty mutually to surrender. The jealousies thus excited were fanned into a violent flame by the artful measures of Alcibiades, a young Athenian, who now began to rise into political power, and whose genius and character subsequently exercised a strong influence upon the affairs of Athens.