Chapter 4 provides an overview of the history and development of the Shiʿites. It defines the Shiʿa as those who elevate devotion and personal allegiance to the Prophet and his family as the most crucial element and sign of submission to God. This distinguishes Shiʿism from what is called ʿAlīd loyalism, which is devotion to the Prophet and his family that is widespread among Muslims. After reviewing the issues that led to the formation of the Shiʿites, the chapter traces the militant ghulāt movements of the early period, the Zaydīs and the Alevi and ʿAlawī movements. It then moves to consider the quietist Shiʿa, discussing the Imāmī movement before moving on to the groups that splintered off from it: both the “Twelver” (Ithnā-ʿAsharī) and Ismāʿīlī Shiʿite movements.