Answer:
Abbasid caliph Harun al-Rashid
Step-by-step explanation:
This period is traditionally understood to have begun during the reign of the Abbasid caliph Harun al-Rashid (786 to 809) with the inauguration of the House of Wisdom in Baghdad, the world's largest city by then, where Muslim scholars and polymaths from various parts of the world with different cultural backgrounds
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