Ardashir was a descendant of Sassan. His father, Papak, was a vassal of the chief petty king in Persis, Gochihr. Papak killed Gochihr and took the title of king and Ardashir succeeded him to the throne in 208.

Ardashir defeated the Parthian army and entered the capital of Ctesiphon where he was crowned with the imperial title 'king of kings'.

His Sassaninian Empire was called neo-Persian because of his appeal to Persia's past. One important link to the past was the recall of the ancient religion of Zoroastrianism, which became the new state religion.

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