related to Diya Aku, a King of the Medes from 700 BC. According to Greek records, this territory was called 'Ekbatan' and 'Hegmataneh' by this King, thus transformed into a huge capital.

During the Parthian era, Ctesiphon became capital of Persia, and Hamedan became the summer capital and residence of the Parthian rulers. After the Parthians, the Sassanids constructed their summer palaces in Hamedan as well.