MITHRADATES I  . (Arsaces VI.), successor of his brother, Phraates I., came to the Parthian throne about 175 B.C . The first event of his reign was a war with Eucratides of Bactria, who tried to create a great Greek empire n8nni Kt°;saof . in the East . At last, when Eucratides had been murdered by his son about 15o, Mithradates was able to occupy some districts on the border of Bactria and to conquer Arachosia (Kandahar); he is even said to have crossed the Indus (Justin 41, 6; Strabo xi . 515, 517; cf . Orosius v . 4, 16; Diod . 33, 18) . Meanwhile the Seleucid kingdom was torn by internal dissensions, fostered by Roman intrigues . Phraates I. had already conquered eastern Media, about Rhagae (Rai), and subjected the Mardi on the border of the Caspian (Justin 41, 5; Isidor . Charac .

7) . Mithradates I. conquered the

rest of Media and advanced towards the Zagros chains and the Babylonian plain . In a war against the Elymaeans (in Susiana) he took the Greek town Seleucia on the Hedyphon, and forced their king to become a vassal of the Parthians (Justin 41, 6; Strabo xv . 744) . About 141 he must have become master of Babylonia . By Diodorus 33, 18 he is praised as a mild ruler; and the fact that from 140 he takes on his coins the epithet Philhellen (W . Wroth, Catalogue of the Coins of Parthia, p . 14 seq.; till then he only calls himself " the great king Arsakes ") shows that he tried to conciliate his Greek subjects . The Greeks, however, induced Demetrius II . Nicator to come to their deliverance, although he was much pressed in Syria by the pretender Diodotus Tryphon . At first he was victorious, but in 138 he was defeated . Mithradates settled him with a royal household in Hyrcania and gave him his daughter Rhodogune in marriage (Justin 36, 1, 38, 9; Jos .

Ant . 13, 5, 11; Euseb . Chron . I . 257; Appian Syr . 67) . Shortly afterwards Mithradates I. died, and was succeeded by his son Phraates II . He was the real founder of the Arsacid Empire .