One year later, the Muslim Arabs invaded Persia, and by 636, they were camping at Al-Qādisiyyah, a city close to Ctesiphon, the capital of the Sasanian Empire.
[2] During the battle, the Sasanian army was defeated, and Shahriyar, along with Musel, Bahman, Jalinus and Rostam, were killed.
Kanadbak then fled to his domains in Abarshahr, and is later mentioned in 652, when Abdullah ibn Aamir invaded Khorasan, and made a treaty with him.
However, the Karenids of Nishapur under Burzin Shah and Sawar Karin, were threatening both Kanadbak and Abdullah, and reclaimed territory in Khorasan which was once under their control.
[3] In promise of regaining his lost territories, Kanadbak agreed to aid Abdullah in capturing Nishapur from the Karenid rebels.