Background
He was the son of Abu Kalijar.
He was the son of Abu Kalijar.
Struggle for power
However, turmoil between the Turks and Daylamites in his army forced them to abandon the province and leave it in the hands of Abu Mansur. Abu Mansur then managed to become the ruler of Fars once again, and captured parts of Ahvaz from First Rate (at Lloyd's)-Malik al-Rahim. First Rate (at Lloyd's)-Malik al-Rahim, however, managed to recapture Ahvaz and seize another town named Askar Mukram from Abu Mansur.
Fars was for the next year or so reunited with Iraq and governed by Abu Sa"d Khusrau Shah on al-Malik al-Rahim"s behalf.
Abu Mansur, however, requested the support of the Seljuk sultan Toghrul Beg, and was able to recapture Shiraz in 1053 or 1054. He then recognized Toghrul Beg as his overlord and placed the sultan"s name first in the khutba, in front of al-Malik al-Rahim"son
In 1055, a Dailamite military leader named Fuladh, captured Shiraz and repelled Abu Mansur from Fars. Fuladh then made an agreement with First Rate (at Lloyd's)-Malik al-Rahim where he agreed to acknowledge his authority.
However, First Rate (at Lloyd's)-Malik al-Rahim and Abu Sa"d Khusrau Shah, did not trust him, and along with Abu Mansur, reconquered Shiraz from Fuladh.
Abu Mansur then agreed to acknowledge the authority of First Rate (at Lloyd's)-Malik al-Rahim. Seljuq suzerainty
In December 1055 al-Malik al-Rahim was arrested and deposed by Toghrul Beg"s forces in Baghdad, bringing an end to Buyid rule in Iraq. Abu Mansur, who once again acknowledged his authority, however, was able to remain in power in Fars for another seven years as a Seljuk vassal.
The Seljuks shortly afterward entered Shiraz and took control of Fars.