1. _Bithynia._ As early as the Persian period, mention is made of two kings in Bithynia, Dydalsus and Botyras. The son of the latter, Bias, B. C. 378-328, made head against Caranus, one of Alexander's generals; as did also his son Zipoetas, _d._ 281, against Lysimachus.--Lycomedes I. _d._ 248. He called the Gauls over from Thrace, 278, and with their assistance deposed his brother Zipoetas; the Gauls in consequence kept their footing in Galatia, and were for a long time an object of terror to Asia Minor. Zelas, _d._ about 232; established his dominion after a war with his half-brothers. Prusias I. son-in-law and ally of Philip II. of Macedon, _d._ 192. He sided with the Rhodians in the commercial war against Byzantium, 222, (see above, p. 282.) and directed his arms, 196, against Heraclea, a Grecian city in Bithynia, with a respectable territory along shore. Prusias II. waged war against Eumenes II. at the instigation of Hannibal, who had fled to his court, 184; he was subsequently about to deliver up the fugitive to the Romans; had not Hannibal put a period to his existence, 183: this king likewise waged war against Attalus II. 153; in both these contests Rome acted as mediator. Prusias, who had the meanness to style himself a freedman of the Romans, was dethroned by his own son, Nicomedes II. _d._ 92; a confederate of Mithridates the Great, with whom, nevertheless, he afterwards fell out concerning the appropriation of Paphlagonia and Cappadocia. Nicomedes was murdered by his son Socrates, who was, however, compelled to flee; in consequence of which Nicomedes III. succeeded to the crown. Deposed by Mithridates, who supported his half-brother Socrates, he was reinstated by Rome, 90. Having, however, at the instigation of the Romans, 89, attacked Mithridates, he was defeated and expelled in the first Mithridatic war, now kindled; but in the peace of 85, he was again reinstated by Sulla. At his death, 75, he bequeathed Bithynia to the Romans; and this legacy gave rise to the third Mithridatic war. VAILLANT, _Imperium Arsacidarum_, vol. ii. See below. SEVIN, _Recherches sur les rois de Bithynie_; inserted in the _Mem. de l'Academie des Inscript._ vol. xii.