Sanjar-Shah was the amir of central Khurasan from 1185 or 1186 until 1187.[1] His short reign was ended by a Khwarezmid invasion and resulted in the takeover of Nishapur by Khwarezm.
Sanjar-Shah succeeded his father Toghan-Shah after the latter's death in either 1185 or 1186, although his atabeg Mengli Beg held actual power.[2] In 1186 the Khwarezmshah Tekish, having been informed on the instability in Khurasan, led an army south in 1186 and laid siege to Shadyakh, where Sanjar-Shah and Mengli Beg were residing (Shadyakh was a suburb of Nishapur, which had been Sanjar-Shah's father's capital, but which had been heavily damaged by Ghuzz raids). A second siege by Tekish's army in 1187 ended with the capture of Shadyakh and both Sanjar-Shah and his atabeg. Mengli Beg was executed, while Sanjar-Shah was carried off to Khwarezm; the government of Nishapur was given over to Tekish's son Malik-Shah.[1] Despite this, Sanjar-Shah continued to collude with anti-Khwarezmid elements in Nishapur; in retaliation the shah ordered his blinding.