KARBALA, a city located sixty-five miles southwest of Baghdad, constitutes the pivot of devotion for more than a hundred million Shīʿī Muslims. Although the estimated population of this palm-grove-laden city is approximately 500,000, during seasons of pilgrimage it draws more than a million devotees. The city owes its significance to the battle that was waged on its soil in 680 CE between Ḥus b. ʿAli, the younger grandson of the prophet Ṃuhammad, and Yazid b. Muʾawiya, the ruling head of the Ummayad dynasty at the time. During the battle, Ḥusayn and a small group of followers and family members were killed by the forces of Yazid after refusing to acknowledge the latter as a legitimate authority. Ḥusayn, for his devotees, has remained the most significant martyr of Islam, Sayyid al-shuhada, and Karbala, the site of this martyrdom, Mashhad al-Ḥusyan. For the Shīʿī Muslims, Ḥusayn is also one of...