 The Achaemenid harem served as a model for later Iranian empires, and the institution remained almost unchanged.Little is known about the harems of the Parthians, but the information about the Sasanian harem reveals a picture that closely mirrors Achaemenid customs.A peculiar characteristic of the Sasanian royalty and aristocracy, which was attested in later times under the Safavid and Qajar empires, was that the highest female rank was not necessarily given to the chief wife, but could be held by a daughter or a sister.