Antiochus III, Invasion of Parthia by
PRINCIPAL COMBATANTS: Syria vs. Parthia and Bactria
PRINCIPAL THEATER(S): Parthia
MAJOR ISSUES AND OBJECTIVES: Antiochus III’s lust for
OUTCOME: Antiochus was victorious, forcing Arsaces III,
king of Parthia, to accept Seleucid suzerainty.
APPROXIMATE MAXIMUM NUMBER OF MEN UNDER ARMS:
CASUALTIES: Unknown, but apparently disastrous for
Parthia and Bactria
TREATIES: No document exists
Antiochus III (c. 242–187 B.C.E.), known as Antiochus the
Great, was the Seleucid king of the Hellenistic Syrian
Empire from 223 to 187 B.C.E. His hunger for new territory
was insatiable and led him to expand the empire in the
east, but also brought defeat in the west as he failed in his
challenge to Roman power. Among his greatest triumphs
was the invasion of Parthia in 209 B.C.E. He defeated the
forces of King Arsaces III (212–171 B.C.E.) and, after occupying
Hecatom pylos, Arsaces’s capital southeast of the
Caspian Sea, drove the Parthion king into a desperate
alliance with Euthydemus (fl. late third century), king of
Bactria. In 208 at the Arius River, Antiochus met the combined
forces of Arsaces and Euthydemus. Severely
wounded early in the battle, Antiochus nevertheless led his
army to complete victory against the larger allied force.
Both the Bactrians and the Parthians suffered heavy losses,
but Arsaces III acknowledged the suzerainty of the Seleucids,
and Antiochus allowed him to continue to rule.
See also BACTRIAN-SYRIANWAR; EUTHYDEMUS’S REVOLT.
Further reading: John Ma, Antiochus III and the Cities of
Western Asia Minor (Oxford: Oxford University Press, 1999).