In the rich tapestry of Islamic history, the schism between Sunnis and Shi'a stands as a defining rift, born from the ashes of the Prophet Muhammad's passing in 632. Laurence Louër, in her masterful exploration "Sunnis and Shi'a," delves deep into this enduring divide, tracing its origins to the contentious debate over Muhammad’s successor. Louër navigates the complex narrative with the skill of a seasoned historian, transporting readers from the initial discord surrounding Ali's rightful place as leader, through centuries of theological and political evolution, to the contemporary manifestations of this ancient schism. Through her lens, the Sunni-Shi'a split is revealed not merely as a religious disagreement but as a profound question about the nature of Islamic authority itself. Louër's work transcends a simple recounting of historical events, offering an insightful analysis into how the Sunni-Shi'a divide has been both a source of conflict and coexistence throughout Islamic history. With a keen eye on the socio-political undercurrents, she unveils how this schism has been manipulated or mollified by political powers to suit their needs, from consolidating elite rule to challenging state authority. "Sunnis and Shi'a" is not just a chronicle of religious discord; it is a compelling narrative that sheds light on the nuanced interplay between faith, power, and identity in the Muslim world. Louër challenges prevailing perceptions, presenting a nuanced perspective on the historical and contemporary dynamics of the Sunni-Shi'a divide, making this book a critical read for anyone seeking to understand the complexities of Islamic sectarianism and its far-reaching implications for global politics.