Seleucids and Parthians

Alexander did not stay long. After defeating Darius III at Gaugamela in 331 BCE, he marched as far as the Indus, then returned to Susa, where in 324 BCE he and some eighty of his officers married Iranian brides in a mass wedding. He died at Babylon the following year, not yet 33. His generals divided his conquests. One of them, Seleucus, won most of the Asian territories, and his heirs, the Seleucids, ruled Iran from cities founded or refounded on Greek lines. Greek became a language of government, and Greek-style coins, theatres and gods spread east. On the Iranian plateau, though, the Seleucid grip was never firm.

Horsemen from the north-east

In the 3rd century BCE a people called the Parni, led by a chief named Arsaces, settled in the province of Parthia, south-east of the Caspian, in lands now divided between north-eastern Iran and Turkmenistan. Their dynasty, the Arsacids, later counted its years from 247 BCE. Over the next century they pushed west, and under Mithridates I, around 141 BCE, they took Mesopotamia. Ctesiphon, on the Tigris near modern Baghdad, became their great royal city. The Parthians ruled lightly. They left local kings in place and struck coins with Greek legends calling the king philhellenos, 'friend of the Greeks', while keeping Iranian customs of kingship. At Nisa, an early royal seat near modern Ashgabat, excavators found ivory drinking horns carved with scenes from Greek myth.

Rome learned about Parthia the hard way. In 53 BCE the Roman general Crassus invaded Mesopotamia and met a Parthian army at Carrhae, in what is now south-eastern Turkey. Mounted archers, resupplied with arrows from a camel train, shot down the legions; Crassus was killed and the legionary standards captured. The trick of turning in the saddle to shoot while apparently retreating became known as the 'Parthian shot', probably the origin of the English 'parting shot'.

For nearly three centuries the two empires fought over Armenia and Mesopotamia without either winning a lasting victory. The Parthians' end came from within. In 224 CE Ardashir, a ruler from Fars, defeated the last Parthian king, Artabanus IV, and founded a new dynasty. Later Persian tradition, shaped by the victors, remembered the Parthians only dimly; Ferdowsi's Shahnameh, the 'Book of Kings', passes over them quickly.