CLEON (d. 422 B.C.), Athenian politician during the Peloponnesian War, was the son of Cleaenetus, from whom he inherited a lucrative tannery business. He was the first prominent representative of the commercial class in Athenian politics. He came into notice first as an opponent of Pericles, to whom his advanced ideas were naturally unacceptable, and in his opposition somewhat curiously found himself acting in concert with the aristocrats, who equally hated and feared Pericles. During the dark days of 430, after the unsuccessful expedition of Pericles to Peloponnesus, and when the city was devastated by the plague, Cleon headed the opposition to the Periclean régime. Pericles was accused by Cleon of maladministration of public money, with the result that he was actually found guilty (see Grote’s Hist. of Greece, abridged ed., 1907, p. 406, note 1). A revulsion of feeling, however, soon took place. Pericles was reinstated, and Cleon now for a time fell into the background. The death of Pericles (429) left the field clear for him. Hitherto he had only been a vigorous opposition speaker, a trenchant critic and accuser of state officials. He now came forward as the professed champion and leader of the democracy, and, owing to the moderate abilities of his rivals and opponents, he was for some years undoubtedly the foremost man in Athens. Although rough and unpolished, he was gifted with natural eloquence and a powerful voice, and knew exactly how to work upon the feelings of the people. He strengthened his hold on the poorer classes by his measure for trebling the pay of the jurymen, which provided the poorer Athenians with an easy means of livelihood. The notorious fondness of the Athenians for litigation increased his power; and the practice of “sycophancy” (raking up material for false charges; see Sycophant), enabled him to remove those who were likely to endanger his ascendancy. Having no further use for his former aristocratic associates, he broke off all connexion with them, and thus felt at liberty to attack the secret combinations for political purposes, the oligarchical clubs to which they mostly belonged. Whether he also introduced a property-tax for military purposes, and even held a high position in connexion with the treasury, is uncertain. His ruling principles were an inveterate hatred of the nobility, and an equal hatred of Sparta. It was mainly through him that the opportunity of concluding an honourable peace (in 425) was lost, and in his determination to see Sparta humbled he misled the people as to the extent of the resources of the state, and dazzled them by promises of future benefits.

In 427 Cleon gained an evil notoriety by his proposal to put to death indiscriminately all the inhabitants of Mytilene, which had put itself at the head of a revolt. His proposal, though accepted, was, fortunately for the credit of Athens, rescinded, although, as it was, the chief leaders and prominent men, numbering about 1000, fell victims. In 425, he reached the summit of his fame by capturing and transporting to Athens the Spartans who had been blockaded in Sphacteria (see Pylos). Much of the credit was probably due to the military skill of his colleague Demosthenes; but it must be admitted that it was due to Cleon’s determination that the Ecclesia sent out the additional force which was needed. It was almost certainly due to Cleon that the tribute of the “allies” was doubled in 425 (see Delian League). In 422 he was sent to recapture Amphipolis, but was outgeneralled by Brasidas and killed. His death removed the chief obstacle to an arrangement with Sparta, and in 421 the peace of Nicias was concluded (see Peloponnesian War).

The character of Cleon is represented by Aristophanes and Thucydides in an extremely unfavourable light. But neither can be considered an unprejudiced witness. The poet had a grudge against Cleon, who had accused him before the senate of having ridiculed (in his Babylonians) the policy and institutions of his country in the presence of foreigners and at the time of a great national war. Thucydides, a man of strong oligarchical prejudices, had also been prosecuted for military incapacity and exiled by a decree proposed by Cleon. It is therefore likely that Cleon has had less than justice done to him in the portraits handed down by these two writers.

Authorities.—For the literature on Cleon see C. F. Hermann, Lehrbuch der griechischen Antiquitäten, i. pt. 2 (6th ed. by V. Thumser, 1892), p. 709, and G. Busolt, Griechische Geschichte, iii. pt. 2 (1904), p. 988, note 3. The following are the chief authorities:—(a) Favourable to Cleon.—C. F. Ranke, Commentatio de Vita Aristophanis (Leipzig, 1845); J. G. Droysen, Aristophanes, ii., introd. to the Knights (Berlin, 1837); G. Grote, Hist. of Greece, chs. 50, 54; W. Oncken, Athen und Hellas, ii. p. 204 (Leipzig, 1866); H. Müller-Strübing, Aristophanes und die historische Kritik (Leipzig, 1873); J. B. Bury, Hist. of Greece, i. (1902). (b) Unfavourable.—J. F. Kortüm, Geschichtliche Forschungen (Leipzig, 1863), and Zur Geschichte hellenischen Staatsverfassungen (Heidelberg, 1821); F. Passow, Vermischte Schriften (Leipzig, 1843); C. Thirlwall, Hist. of Greece, ch. 21; E. Curtius, Hist. of Greece (Eng. tr.) iii. p. 112; J. Schvarcz, Die Demokratie (Leipzig, 1882); H. Delbrück, Die Strategie des Perikles (Berlin, 1890); E. Meyer, Forschungen zur alten Geschichte, ii. p. 333 (Halle, 1899). The balance between the two extreme views is fairly held by J. Beloch, Die attische Politik seit Perikles (Leipzig, 1884), and Griechische Geschichte, i. p. 537; and by A. Holm, Hist. of Greece, ii. (Eng. tr.), ch. 23, with the notes.