[6] Tabaristan was subsequently made a regular province of the caliphate, ruled from Amul by an Arab governor, although the local dynasties of the Bavandids, Qarinvandids, the Zarmihrids and Baduspanids, formerly subject to the Dabuyids, continued to control the mountainous interior as tributary vassals of the Abbasid government.

[9] Due to the regional prominence of the Baduspanids, Ruyan became known as Rustamdar in the Mongol era, a deformed form of their regnal title, ustandar, which they had used since the rule of Shahriyar III ibn Jamshid (r. 937–949).

[2][10] The Baduspanids were briefly deposed from power by the Mar'ashis, who ruled Rustamdar from 1381 till 1390, when they decided to install Baduspanid prince Sa'd al-Dawla Tus on the throne in Rustamdar to challenge the Afrasiyabid prince Iskandar-i Shaykhi who accompanied the Turco-Mongol ruler Timur (r. 1370–1405), who intended to conquer Mazandaran.

After his death, a dynastic struggle followed, which resulted in his kingdom being split up by his sons Iskandar IV and Ka'us II, in Kojur and Nur respectively.

[1] The Baduspanid dynasty was never to be united again, with the two branches ruling separately until they were eventually deposed in 1590s by the Safavid monarch of Iran, Abbas the Great (r. 1588–1629).