(Δημήτριος), king of BACTRIA, son of Euthydemus. Polybius mentions (11.34), that when Antiochus the Great invaded the territories of Euthydemus, the latter sent his son Demetrius, then quite a youth, to negotiate with the Syrian king; and that Antiochus was so much pleased with the young man's appearance and manners, that he confirmed Euthydemus in his sovereignty, and promised one of his own daughters in marriage to Demetrius. The other notices we possess of this prince are scanty and confused; but it seems certain (notwithstanding the opinion to the contrary advanced by Bayer, Hist. Regni Graecorum Bactriani, p. 83), that Demetrius succeeded his father in the sovereignty of Bactria, where he reigned at least ten years. Strabo particularly mentions him as among those Bactrian kings who made extensive conquests in northern India (Strab. 11.11.1), though the limit of his acquisitions cannot be ascertained. Justin, on the con trary, calls him "rex Indorum" (41.6), and speaks of him as making war on and besieging Eucratides, king of Bactria. Mionnet (Suppl. vol. viii. p. 473) has suggested that there were two Demetrii, one the son of Euthydemus, the other a king of northern India; but it does not seem necessary to have recourse to this hypothesis. The most probable view of the matter is, that Eucratides revolted from Demetrius, while the latter was engaged in his wars in India, and established his power in Bacteria proper, or the provinces north of the Hindoo Koosh, while Demetrius retained the countries south of that barrier. Both princes may thus have ruled contemporaneously for a considerable space of time. (Comp. Wilson's Ariana, pp. 228-231; Lassen, Gesch. der Bactr. Könige, p. 230; Raoul Rochette, Journ. des Savans, for 1835, p. 521.) It is probably to this Demetrius that we are to ascribe the foundation of the city of Demetrias in Arachosia, mentioned by Isidore of Charax (p. 8, ed. Hudson; see Lassen, p. 232). The chronology of his reign, like that of all the Bactrian kings, is extremely uncertain: his accession is placed by M. R. Rochette in B. C. 190 (Journ. des Savans, Oct. 1835, p. 594), by Lassen in 185 (Gesch. der Bactr. Könige, p. 282), and it seems probable that he reigned about 20 or 25 years. (Wilson's Ariana, p. 231.)