Parthians are mentioned in Acts 2:9 among the sojourners in Jerusalem on the Day of Pentecost. They were probably Jews who had become naturalized in Parthia, ‘Jews of the Dispersion,’ with possibly a few Parthian proselytes. Their ruler at this time was Arsaces XIX. (Artabanus III.), and their kingdom extended from Mesopotamia eastwards to the borders of India. The Parthians at first inhabited the mountainous country south of the Caspian Sea, between Media and Bactriana. Strabo (xi. 9. 2), Arrian (frag. 1), and Justin (xli. 1-4) agree in describing them as Scythians brought into this region by Sesostris. However this may be, they came under Persian rule in the time of Darius Hystaspis, and remained loyal to the Persian kings till Alexander the Great overthrew Darius Codomannus (333 b.c.) and conquered all his territory. Thereafter the Parthians acknowledged the suzerainty of the Seleucidae till 256 b.c., when they revolted under Arsaces I., who became founder of a dynasty which lasted till c._ a.d. 226.
Rome found the Parthians a difficult people to subdue, and the conflicts between the two nations were many and long-continued. Sometimes Rome prevailed; sometimes Parthia held its own. The Parthian soldiers were skilled horsemen and archers. They could move quickly on military campaigns, and shoot arrows with great precision while riding at full speed. Hence they were able to harass even the highly disciplined armies of Rome. The Parthians were not a literary people, and fell below the Persians, and very much below the Greeks, both in civilization and in art._
A. W. Cooke.