Parthian Empire, 44 BCE to 138 CE. The Parthian Empire (247BCE– 224CE) was a major political and cultural power in ancient Iran. Mithridates I of Parthia (r. c. 171–138 BC) greatly expanded the empire by seizing Media & Mesopotamia from the Seleucids. At its height, the Parthian Empire stretched from the northern reaches of the Euphrates to eastern Iran. The empire, located on the Silk Road trade route between the Roman Empire and Han Empire of China, became a center of trade and commerce.