عضد الدولة
As part of the settlement between Rukn al-Dawla and his eldest son 'Adud al-Dawla in early 976, Mu'ayyad al-Dawla was to receive Hamadan upon his father's death, in exchange for recognizing 'Adud al-Dawla as senior amir. Only a year later, Rukn al-Dawla's second son Fakhr al-Dawla, who ruled in Ray, rebelled against 'Adud al-Dawla's authority. Mu'ayyad al-Dawla mobilized in support of 'Adud al-Dawla, forcing Fakhr al-Dawla to flee to the Ziyarids of Gorgan and Tabaristan. This did not stop the two Buyids; 'Adud al-Dawla took Gorgan in 980, while Mu'ayyad al-Dawla gained control of Tabaristan in 981. Mu'ayyad al-Dawla was entrusted with the newly captured provinces as 'Adud al-Dawla's subordinate.