The House of Ispahbudhan or the House of Aspahbadh was one of the seven Parthian clans of the Sasanian Empire. Like the Sasanians, they claimed descent from the Achaemenids. They also claimed descent from the legendary Kayanid figure Isfandiyar, who was the son of the Vishtaspa, who according to Zoroastrian sources was one of Zoroaster's early followers.
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House of Ispahbudhan Wikipedia(Text) CC BY-SA