Chalcideus, the Spartan commander, with whom, in the spring and summer of 412 BC, the year after the defeat at Syracuse, Alcibiades threw the Ionian subject allies of Athens into revolt. He had been appointed commander (evidently not high-admiral) during the previous winter in the place of Melanchridas, the high- admiral on occasion of the ill omen of an earthquake ; and on the news of the blockade of their ships at Peiraeus, the Spartans, but for the persuasions of Alcibiades, would have kept him at home altogether. Crossing the Aegaean with only five ships, they effected the revolt first of Chios, Erythrae, and Clazomenae; then, with the Chian fleet, of Teos; and finally, of Miletus, upon which ensued the first treaty with Tissaphernes. From this time Chalcideus seems to have remained at Miletus, watched by an Athenian force at Lade. Meanwhile, the Athenians were beginning to exert themselves actively, and from the small number of Chalcideus' ships, they were able to confine him to Miletus, and cut off his communication with the disaffected towns; and before he could be joined by the high-admiral Astyochus (who was engaged at Chios and Lesbos on his first arrival in Ionia),

Chalcideus was killed in a skirmish with the Athenian troops at Lade in the summer of the same year (412 BC.) in which he had left Greece. (Thuc. viii. 6, 8, 11, 17, 24.)