Al-Hakim bi-Amr Allah was the sixth caliph of the Fatimid Caliphate, ruling from 996 to 1021 CE. He is known for his eccentric behavior and controversial policies, which included the persecution of certain religious groups. His reign was marked by significant architectural developments in Cairo, including the construction of the Al-Hakim Mosque. Despite his erratic rule, Al-Hakim is also remembered for his contributions to philosophy and science. He established the Dar al-Hikma, a center for learning that attracted scholars from various backgrounds. His legacy remains complex, blending both cultural advancements and political turmoil during the Fatimid era.