Harun al-Rashid (766-809) was the fifth caliph of the Abbasid dynasty. During his reign the power and prosperity of the dynasty was at its height, though it has also been argued that its decline began at that time.

In 750 the Abbasid dynasty replaced the Umayyad as rulers of the Islamic Empire, and for a generation they were busy consolidating their rule and overcoming internal disorders. They moved the capital eastward from Damascus to their new city of Baghdad. By 786 the reorganization of the empire was bearing fruit in greater trade and greater wealth, which made possible the luxury now associated with the caliphal court.

Harun al-Rashid was born at Reyy near Teheran in 766 (or perhaps 763), the third son of the third Abbasid caliph, Mohammed al-Mahdi. His mother was Khayzuran, a Yemeni slave girl, later freed, who through her husband and son came to have great political influence. As...