In 484, Peroz I, the grandfather of Khosrow I Anushirvan (r. 531–579), was killed in the Battle of Herat (484) by the Hephthalites and allowed them to annex much of Khorasan from the Sasanians.

After a stable peace agreement with the Byzantines in the west, Khosrow I was able to focus his attention on the Eastern Hephthalites and avenge the death of his grandfather.

According to the account of Firdausi in the Shahname, the Hephthalites were supported by troops from Balkh, Shughnan, Amol, Zamm, Khuttal, Termez and Washgird.

[8] This was much to the dislike of Khosrow I, who considered the Turkic collaboration with the Hephthalites to pose a danger for his rule in the east, and thus marched towards the Sasanian-Turkic border in Gurgan.

The alliance contained a treaty that made it obligatory for Faghanish to be sent to the Sasanian court in Ctesiphon and gain the approval of Khosrow for his status as Hephthalite king.