The reason for the war is Rostam's disobedience to Esfandiyār's father, Goshtāsp, the king of Iran.

Esfandiyar was commissioned to invade that country and capture Rostam, the leader of the Zabolians.

[2] Esfandiyar departed with a small number of troops and camped near a river near the city of Zabul.

He sent his son Bahman to convey the message of the Shah of Iran to the leaders of Zabul.

Esfandiyar had demanded a monarchy from his father, but Goshtasp's condition was to bring Rostam into captivity in the Iranian capital.