CALLIAS, tyrant of Chalcis in Euboea. With the assistance of Philip II. of Macedon, which he hoped to obtain, he contemplated the subjugation of the whole island. But finding that Philip was unwilling to help him, Callias had recourse to the Athenians, although he had previously (350 B.C.) been engaged in hostilities with them. With the support of Demosthenes, he was enabled to conclude an alliance with Athens, and the tribute formerly paid by Eretria and Oreus to Athens was handed over to him. But his plan of uniting the whole of Euboea under his rule, with Chalcis as capital, was frustrated by Philip, who set up tyrants chosen by himself at Eretria and Oreus. Subsequently, when Philip’s attention was engaged upon Thrace, the Athenians in conjunction with Callias drove out these tyrants, and Callias thus became master of the island (Demosthenes, De Pace, p. 58; Epistola Philippi, p. 159; Diod. Sic. xvi. 74). At the end of his life he appears to have lived at Athens, and Demosthenes proposed to confer the citizenship upon him (Aeschines, Contra Ctesiphontem, 85, 87).