From Smith's Dictionary of Greek and Roman Biography and Mythology (London, 1880)
ACHAEUS ('Achaios), according to nearly all traditions a son of Xuthus and Creusa, and consequently a brother of Ion and grandson of Hellen. The Achaeans regarded him as the author of their race, and derived from him their own name as well as that of Achaia, which was formerly called Aegialus. When his uncle Aeolus in Thessaly, whence he himself had come to Peloponnesus, died, he went thither and made himself master of Phthiotis, which now also received from him the name of Achaia. (Paus. vii. 1. § 2 ; Strab. viii. p. 383; Apollod. i. 7. § 3.) Servius (ad Aen. i. 242) alone calls Achaeus a son of Jupiter and Pithia, which is probably miswritten for Phthia.
ACHAEUS ('Achaios), son of Andromachus whose sister Laodice married Seleucus Callinicus, the father of Antiochus the Great. Achaeus himself married Laodice, the daughter of Mithridates, king of Pontus, (Polyb. iv. 61. § 4, viii. 22. § 11.) He accompanied Seleucus Ceraunus, the son of Callinicus, in his expedition across mount Taurus against Attalus, and after the assassination of Seleucus revenged his death ; and though he might easily have assumed the royal power, he remained faithful to the family of Seleucus. Antiochus the Great, the successor of Seleucus, appointed him to the command of all Asia on this side of mount Taurus, B. C. 223. Achaeus recovered for the Syrian empire all the districts which Attalus had gained ; but having been falsely accused by Hermeias, the minister of Antiochus, of intending to revolt, he did so in self-defence, assumed the title of king, and ruled over the whole of Asia on this side of the Taurus. As long as Antiochus was engaged in the war with Ptolemy, he could not march against Achaeus; but after a peace had been concluded with Ptolemy, he crossed the Taurus, united his forces with Attalus, deprived Achaeus in one campaign of all his dominions and took Sardis with the exception of the citadel. Achaeus after sustaining a siege of two years in the citadel at last fell into the hands of Antiochus B. c. 214, through the treachery of Bolis, who bad been employed by Sosibius, the minister of Ptolemy, to deliver him from his danger, but betrayed him to Antiochus, who ordered him to be put to death immediately. (Polyb. iv. 2. § 6, iv. 48, v. 40. § 7, 42, 57, vii. 15-18, viii. 17-23.)
ACHAEUS ('Achaios) of Eretria in Euboea, a tragic poet, was born B. C. 484, the year in which Aeschylus gained his first victory, and four years before the birth of Euripides. In B. C. 477, he contended with Sophocles and Euripides, and though he subsequently brought out many dramas, according to some as many as thirty or forty, he nevertheless only gained the prize once. The fragments of Achaeus contain much strange mythology, and his expressions were often forced and obscure. (Athen. x. p. 451, c.) Still in the satyrical drama he must have possessed considerable merit. for in this department some ancient critics thought him inferior only to Aeschylus. (Diog. Laer. ii. 133.) The titles of seven of his satyrical dramas and of ten of his tragedies are still known. The extant fragments of his pieces have been collected, and edited by Urlichs, Bonn, 1834. (Suidas, s. v.) This Achaeus should not be confounded with a later tragic writer of the same name, who was a native of Syracuse. According to Suidas and Phavorinus he wrote ten, according to Eudocia fourteen tragedies. (Urlichs, Ibid.)
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