(Εὐκρατίδης), king of Bactria, was contemporary with Mithridates I. (Arsaces VI.), king of Parthia, and appears to have been one of the most powerful of the Bactritan kings, and to have greatly extended his dominions; but all the events of his reign are involved in the greatest obscurity and confusion. It seems probable that he established his power in Bactria proper, while Demetrius, the son of Euthydemus, still reigned in the Indian provinces south of the Paropamisus [DEMETRIUS]; and, in tlhe course of the wars that he carried on against that prince, he was at one time besieged by him with very superior forces for a space of near five months, and with difficulty escaped. (Justin, 41.6.) At a subsequent period, and probably after the death of Demetrius. he made great conquests in northern India, so that he was said to have been lord of a thousand cities. (Strab.xv. p. 686.) Yet in the later years of his reign he appears to have suffered heavy losses in his wars against Mithridates, king of Parthia, who wrested from him several of his provinces (Strab. xi. pp. 515, 517), though it seems impossible to admit the statement of Justin (41.6), that the Parthian king conquered all the dominions of Eucratides, even as fair as India. It appears certain at least, from the same anthor, that Euecratides retained possession of his. Indian dominions up to the time of his death, and that it was on his return from thence to Bactria that he was assassinated by his son, whom he had associated with himself in the sovereignty. (Justiin, 41.16.) The statements of ancient authors concerning the power and greatness of Eucratides are confirmed by the number of his coins that have been found on both sides of the Paropamisus : on these he bears the title of " the Great." (Wilson's Ariana, p. 235-237.) The date suggested for the commencement of his reign by Bayer, and adopted by Wilson, is 181 B. C.; but authorities differ widely as to its termination, which is placed by Lassen in 160 B. C., while it is extended by Bayer and Wilson to 147 B. C. (See Wilson's Ariana, p. 234-238, where all the points relating to Eucratides are discussed and the authorities referred to.)