Hassan al-Mustadi Ibn Yusuf al-Mustanjid
(1142 - 1180) (المستضئ بأمر الله) was the Abbasid Caliph
from 1170 to 1180. Like his predecessor, he continued to occupy a more or less independent position, with a Vazir and courtly surroundings, and supported by only a small force sufficient for an occasional local campaign. During his reign Saladin
ended the Fatimid caliphate, became the sultan of Egypt and declared his allegiance to the Abbasids. The famous chronicler Ibn Abu-al-Faraj ibn Al-Jawzi
wrote that he reduced the taxes, was very fair with his subjects and built many mosques, schools and ribats.
In 1080 caliph Al-Mustadi died and was succeeded by his son Ahmed (an-Nasir).