Revival and Reform in Islam is at once an intellectual biography of Muhammad al-Shawkani, and a history of a transitional period in Yemeni history. This was a time when a society dominated by traditional Zaydi Shiism shifted to one characterised instead by Sunni reformism. The author traces the origins and outcomes of this transition, presenting the first systematic account of the ways in which the eighteenth- and nineteenth-century reorientation of the Zaydi madhhab, and consequent ‘sunnification’ of Yemeni society, were intricately linked to tensions within the political realm. In advocating juridical systematization of religious belief and practice, Shawkani espoused a socio-religious order which in its dominant features echoed key aspects of Western modernity. Yet he did so in a context bereft of Western ideational influence. This study then presents a textured account of eighteenth-century Islamic reformist thought and challenges the meaning of modernity in an Islamic context.