High Quality Content by WIKIPEDIA articles! Hasan (d. September 976), known as Rukn al-Dawla, was the first Buyid amir of northern and central Iran (c. 935-976). He was the son of Buya. In around 928, Hasan's brother 'Ali joined the services of Makan, who was the Samanid governor of Ray. 'Ali then managed to gain military positions for Hasan and another brother named Ahmad. At the time, Hasan was about thirty years old. When Makan attacked his Samanid overlords and was subsequently defeated by the Ziyarid prince Mardavij, the brothers transferred their allegiance to the latter. In the following years, 'Ali repudiated his subservience to Mardavij and, after some time, managed to create an empire in Fars. During this time, Hasan distinguished himself in the battles over that province. Mardavij, however, marched south and forced 'Ali to recognize his authority in around 934. Hasan was sent to Madavij's court as a hostage. The death of Mardavij in 935 allowed Hasan to escape, and also provided an opportunity for the Buyids to expand into central Iran.