(Κλέαρχος), a Spartan, son of Ramphias. In the congress which the Spartans held at Corinth, in B. C. 412, it was determined to employ him as commander in the Hellespont after Chios and Lesbos should be gained from the Athenians ; and in the same year the eleven commissioners, who were sent out from Sparta to take cognizance of the conduct of Astyochus, were entrusted with the discretionary power of despatching a force to the Hellespont under Clearchus. (Thuc. 8.8, 39.) In B. C. 410, he was present at the battle of Cyzicus under Mindarus, who appointed him to lead that part of the force which was specially opposed to Thrasybulus. (Diod. 13.51; Xen. Hell. 1.1.16, &c.; Plut. Alc. 28.) In the same year, on the proposal of Agis, he was sent to Chalcedon and Byzantium, with the latter of which states he had a connexion of hospitality, to endeavour to cut off the Athenian supplies of corn in that quarter, and he accordingly fixed his residence at Byzantium as harmost. When the town was besieged by the Athenians, B. C. 408, Clearchus reserved all the provisions, when they became scarce, for the Lacedaemonian soldiers; and the consequent sufferings of the inhabitants, as well as the general tyranny of his rule, led some parties within the place to surrender it to the enemy, and served afterwards to justify them even in the eyes of Spartan judges when they were brought to trial for the alleged treachery. At the time of the surrender, Clearchus had crossed over to Asia to obtain money from Pharnabazus and to collect a force sufficient to raise the siege. He was afterwards tried for the loss of the town, and fined. (Xen. Hell. 1.1.35, 3.15, &c.; Diod. 13.67; Plut. Alc. 31; Polyaen. 1.47, 2.2.) In B. C. 406 he was present at the battle of Arginusae, and was named by Callicratidas as the man most fit to act as commander, should he himself be slain. (Diod. 13.98.) On the conclusion of the Peloponnesian war, Clearchus, to whom peace was ever irksome, persuaded the Spartans to send him as general to Thrace, to protect the Greeks in that quarter against the Thracians. But by the time he had reached the isthmus, the ephors repented their selection of him, and sent an order for his recall. He proceeded however to the Hellespont in spite of it, and was consequently condemned to death by the authorities at home. At Byzantium, where he took up his residence, he behaved with great cruelty, and, having put to death many of the chief citizens and seized their property, he raised a body of mercenaries with the money, and made himself master of the place. The Spartans, according to Diodorus, having remonstrated with him to no purpose, sent a force against him under Panthoides; and Clearchus, thinking it no longer safe to remain in Byzantium, withdrew to Selymbria. Here he was defeated and besieged, but effected his escape by night, and passing over to Asia, proceeded to the court of Cyrus. The prince, whose object was to collect, without exciting suspicion, as many troops as possible for his intended expedition against his brother, supplied Clearchus with a large sum of money, with which he levied mercenaries, and employed them, till Cyrus should need their services, in protecting the Greeks of the Thracian Chersonesus against the neighbouring barbarians. Plutarch says,--a statement not very easy to be reconciled with the sentence of death which had been passed against him,--that he received also an order from Sparta to promote in all points the objects of Cyrus. When the prince had set out on his expedition, Clearchus joined him at Celaenae in Phrygia with a body of 2000 men in all, being, according to Xenophon (Xen. Anab. 3.1.10), the only Greek who was aware of the prince's real object. When the actual intention of Cyrus began to be suspected, the Greeks refused to march further, and Clearchus, attempting to force his own troops to proceed, narrowly escaped stoning at their hands. Professing then to come into their wishes, and keeping up a show of variance between himself and Cyrus, he gradually led, not his own forces only, but the rest of his countrymen as well, to perceive the difficulties of their position should they desert the service of the prince, and thus ultimately induced them to advance. When Orontes was brought to trial for his treason, Clearchus was the only Greek admitted into the number of judges, and he was the first to advise sentence of death against the accused. At the battle of Cunaxa, B. C. 401, he commanded the right wing of the Greeks, which rested on the Euphrates; from this position he thought it unsafe to withdraw, as such a step would have exposed him to the risk of being surrounded; and he therefore neglected the directions of Cyrus, who had desired him to charge with all his force the enemy's centre. Plutarch blames him exceedingly for such an excess of caution, and attributes to it the loss of the battle. When the Greeks began their retreat, Clearchus was tacitly recognized as their commander-in-chief, and in this capacity he exhibited his usual qualities of prudence and energy, as well as great strictness in the preservation of discipline. At length, however, being desirous of coming to a better understanding with Tissaphernes, and allaying the suspicions which existed between him and the Greeks in spite of their solemn treaty, Clearchus sought an interview with the satrap, the result of which was an agreement to punish the parties on both sides who had labored to excite their mutual jealousy; and Tissaphernes promised that, if Clearchus would bring his chief officers to him, he would point out those who had instilled suspicion into him against their countrymen. Clearchus fell into the snare, and induced four of the generals and twenty of the lochagi to accompany him to the interview. The generals were admitted and arrested, while the other officers, who had remained without, were massacred. Clearchus and his colleagues were sent to the court of Artaxerxes, and, notwithstanding the efforts of the queen-mother, Parysatis, in their favour, were all beheaded, with the exception of Menon, who perished by a more lingering death. In this account Xenophon and Ctesias in the main agree; but from the latter Plutarch reports besides several apocryphal stories. One of these is, that, while the bodies of the other generals were torn by dogs and birds, a violent wind raised over that of Clearchus a tomb of sand, round which, in a miraculously short space of time, an overshadowing grove of palm-trees arose; so that the king repented much when he knew that he had slain a favourite of the gods. (Xen. Anab. 1.1.9, 2.9, 3. §§ 1-21, 5. §§ 11-17, 6. §§ 1-11, 8. §§ 4-13, 2.1-6.15; Diod. 14.12, 22_26; Plut. Art. 8, 18.)