In 651,
Yazdegerd III was murdered by
Mahuy Suri, the
marzban of
Marw.
Tabaristan was afterwards invaded by the Muslim Arabs, who were defeated at the battle of Ruyan by the Zoroastrian Dabboyids.
Farrukhzad, the previously minister of Yazdegerd, and ruler of Tabaristan, managed to repel the Arabs with the aid of
Gil Gavbara and make a treaty with them. The Arabs then invaded
Khorasan, and made a treaty with the
kanarang of
Tus,
Kanadbak. In the treaty Kanadbak agreed to pay tribute to the Arabs while still remaining in control of his territories in Tus. In order to strengthen the weakened
Karen family, and to reclaim lost Karenid territory, Burzin, along with another Karenid named Sawar Karin, made resistance to the
Arabs and tried to reclaim territory from the
Kanārangīyān family. In promise of regaining his lost territories, Kanadbak agreed to aid Abdullah in capturing
Nishapur from the Karenid rebels. == Battle ==