When Abu'l-Fawaris' brother Sultan al-Dawla became the senior amir of the Buyids in 1012, he appointed Abu'l-Fawaris (thereafter known as Qawam al-Dawla, "Foundation of the State") as governor of Kerman.
With the support of the Ghaznavids, he invaded and occupied Fars.
A counterattack expelled him from that province, but he managed to retain his hold on Kerman.
Sultan al-Dawla died in 1024, and his son Abu Kalijar managed to gain control of Fars.
Eventually, Qawam al-Dawla and Abu Kalijar engaged in hostilities against each other; the fighting ceased only when Qawam al-Dawla died in late 1028.