The reigns of Harun al-Rashid (786–809) and his successors fostered an age of great intellectual achievement. In large part, this was the result of the schismatic forces that had undermined the Umayyad regime, which relied on the assertion of the superiority of Arab culture as part of its claim to legitimacy, and the Abbasids' welcoming of support from non-Arab Muslims. It is well established that the Abbasid caliphs modeled their administration on that of the Sassanids.^[51] Harun al-Rashid's son, Al-Ma'mun (whose mother was Persian), is even quoted as saying:

The Persians ruled for a thousand years and did not need us Arabs even for a day. We have been ruling them for one or two centuries and cannot do without them for an hour.^[52]

A number of medieval thinkers and scientists living under Islamic rule played a role in transmitting Islamic science to the Christian West. In addition, the period saw the recovery of much of the Alexandrian mathematical, geometric and astronomical knowledge, such as that of Euclid and Claudius Ptolemy. These recovered mathematical methods were later enhanced and developed by other Islamic scholars, notably by Persian scientists Al-Biruni and Abu Nasr Mansur.