AD 223-622 Sasanian

Around AD 224 a local ruler, Ardashir, overthrew the Parthians and dominated Iran. He founded a dynasty named after a legendary ancestor called Sasan. The family seat was the city of Istakhr, close to the ruins of Persepolis and the Sasanians deliberately associated themselves with the glories of the Achaemenid empire. Their ambition to restore Iran’s greatness may have been one reason for their conflict with Rome. By the end of his reign Shapur I (241-272) had defeated the Romans in battle and increased the Sasanian Empire from the River Euphrates to the River Indus.

After a short period during which much territory was lost, Sasanian fortunes were restored under Shapur II (reigned 310-379). He re-established control over the Kushans in the east as well as northern Mesopotamia and Armenia. During the 5th century, the Hephthalite Huns to the north and east of Sasanian lands invaded Afghanistan and the Sasanians were forced to pay them tribute. Iran recovered during the reign of Khusrau I (531-579), who defeated the Hephthalites. Khusrau’s death was followed by internal revolts and wars with the Byzantine empire. This weakened Iran, and Arab forces, united under Islam, over-ran the Sasanian Empire through an effective combination of military action and diplomacy. The last Sasanian ruler, Yazdgard III, was murdered at Merv close to the eastern border of his empire in 651.