On the death of Zav his son Garshásp succeeds to the throne, and Afrásiyáb seizes the opportunity to renew the war. Garshásp himself dies, and the Íránians being hard pressed appeal to Zál, who promises that his son Rustam shall come to their assistance. The poet then tells how Zál gave Sám's mace to Rustam, how the latter won his charger Rakhsh, and how Zál led the host against Afrásiyáb, and sent Rustam to fetch Kai Kubád from Mount Alburz to be Sháh in succession to Garshásp.
In the summary in the Dínkard of the lost Kitradád Nask mention is made of Keresásp, who is placed between Kai Kubád and Kai Káús.* Keresásp appears there to be identical with the great hero, of whom an account has been given in the introductory note to Farídún, and if so apparently we must identify Garshásp, the tenth Sháh, with him as well. In the Sháhnáma, however, he is a mere nominis umbra, and Firdausí places him before kai Kubád, the first Sháh of the Kaiánian dynasty, and makes him the son of the preceding Sháh Zav and the last of the Pishdádians. His personality had already, as we have seen in the note above referred to, become split up, and his reign is a blank so far as he is concerned.
The reader will note Rustam's reference to bishops acting as castellans.* In the wars between the Eastern Roman Empire and the Sásánians, bishops and other ecclesiastics often took a very important part in the defence of besieged cities. Thus S. James, the Bishop of Edessa, took a leading part in several successful defences of Nisibis against Sapor II.* The fact of the church militant thus became impressed on the Eastern mind, and by an anachronism not uncommon with him, Firdausí transfers the usages of later times to earlier ages. The reader will note too the vision of the divine Grace of kingship which prepared Kai Kubád for his accession to the throne. It appeared again visibly in the shape of a ram before the accession of Ardshír Pápakán, the first Sháh of the Sásánian dynasty. When it quitted Yima it flew away in the shape of a bird.*