Third Iranian Empire: Parthian Empire (248 BCE – 224 CE)

Parthia was led by the Arsacid dynasty, who reunited and ruled over the Iranian plateau, after defeating the Greek Seleucid Empire, beginning in the late 3rd century BCE, and intermittently controlled Mesopotamia between ca 150 BCE and 224 CE. These were the third native dynasty of ancient Iran (Persia) and lasted five centuries.

Parthia was the arch-enemy of the Roman Empire in the east, limiting Rome's expansion beyond Cappadocia (central Anatolia). By using a heavily-armed and armoured cataphract cavalry, and lightly armed but highly-mobile mounted archers, the Parthians "held their own against Rome for almost 300 years". Rome's acclaimed general Mark Antony led a disastrous campaign against the Parthians in 36BCE in which he lost 32,000 men. By the time of Roman emperor Augustus, Rome and Parthia were settling some of their differences through diplomacy. By this time, Parthia had acquired an assortment of golden eagles, the cherished standards of Rome's legions, captured from Mark Antony, and Crassus, who suffered "a disastrous defeat" at Carrhae in 53BCE.

Parthian remains display classically Greek influences in some instances and retain their oriental mode in others, a clear expression of "the cultural diversity that characterized Parthian art and life". The Parthians were innovators of many architecture designs such as that of Ctesiphon, which later on "influenced European Romanesque architecture".