PARTHIA, the mountainous country south-east of the Cas pian sea, which extends from the Elburz chain eastwards towards Herat, and is bounded on the north by the fertile plain of Hyrcania (about Astrabad) at the foot of the mountains in the corner of the Caspian and by the Turanian desert; on the south by the great salt desert of central Iran. It corresponds to the modern Khorasan. It was inhabited by an Iranian tribe, the Parthava of the inscriptions of Darius; the correct Greek form is ilapevaioc. Parthia became a province of the Achaemenian and then of the Macedonian empire. Seleucus I. and Antiochus I. founded Greek towns: Soteira, Charis, Achaea, Calliope (Ap pian, Syr. 57; Plin. vi. 15 ; cf. Strabo xi. 516) ; the capital of Parthia, the ruins of which are around the present town Damg han, is known only by its Greek name Hecatompylos ("The Hundred-gated"), from the many roads which met there (Polyb. x. 28), and was, according to Appian, founded by Seleucus I. (cf. Curtius vii. 2). In 208 many Greek inhabitants are found in the towns of Parthia and Hyrcania (Polyb. x. 31, I I).
When about 255 B.C. Diodotus had made himself king of Bactria (q.v.), and tried to expand his dominions, the chieftain of a tribe of Iranian nomads (Dahan Scyths) east of the Caspian, the Parni or Aparni, who bore the Persian name Arsaces, fled before him into Parthia.' Here the satrap Andragoras appears to have shaken off the Seleucid supremacy, as he struck gold and silver coins in his own name, on which he wears the diadem, al though not the royal title (Gardner, Numism. Chronicle, 1879 81). He was slain by Arsaces (Justin xli. 4), who occupied Parthia and became the founder of the Parthian kingdom (248 B.c.). The origin and early history of the Parthian kingdom, of which we possess only very scanty information, is surrounded by fabulous legends, narrated by Arrian in his Parthica (preserved in Photius, cod. 58, and Syncellus, p. 539 seq.). Arsaces ruled
for many years. The troubles of the Seleucid empire, and the war of Seleucus II. against Ptolemy III. and his own brother Antiochus Hierax, enabled him not only to maintain himself in Parthia, but also to conquer Hyrcania ; but he was constantly threatened by Diodotus of Bactria (Justin xli. 4). When, about 238 B.C., Seleucus II. was able to march into the east, Arsaces fled to the nomadic tribe of the Apasiacae (Strabo xi. 513 ; cf. Polyb. x. 48). But Seleucus was soon recalled by a rebellion in Syria, and when Diodotus died, Arsaces returned victorious to Parthia; "the day of this victory is celebrated by the Parthians as the beginning of their independence" (Justin xli. 4). Arsaces was pro claimed king at Asaak in the district of Astauene, now Kuchan, iStrabo xi. 515; cf. Justin xli. 4; the Parni are said by Strabo (ibid.) to have immigrated from southern Russia, a tradition wrongly trans ferred to the Parthians themselves by Justin xli. 1, and Arrian ap. Phot. cod. q8.
(ED. M.)