Parthian Empire. Vologases IV (147-191 AD). Tetradrachm Seleukeia on the Tigris, 186/7 AD.

The tetradrachm minted under Vologases IV, reigning from 147 to 191 AD in the Parthian Empire, is emblematic of the Parthian's complex monetary system and their eastern territorial control. Producing coins in Seleukeia on the Tigris, a key Parthian city, this large silver denomination was central to economic transactions and diplomacy. Vologases IV's rule marked a period of relative stability, and his coinage often features traditional Parthian royal iconography blending Hellenistic and Iranian artistic elements. The tetradrachm format itself was a widely recognized currency standard inherited from Greek influence, adapted by the Parthians to suit their imperial needs and to assert their sovereignty amidst Roman rivalry.