Question: who ruled during the golden age of the abbasid caliphate
Answer: 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 , where scholars from various parts of the world with different cultural backgrounds were mandated to gather and translate all of the world 's classical knowledge into the Arabic language .