Unraveling the complex dynamics that created and sustained the hegemony of the four principal schools of Sunni Islamic law necessarily requires an appreciation of the schools’ historical genesis. This book provides the first comprehensive account of the origin and early development of a Sunni legal school, drawing on new evidence from a range of hitherto unstudied primary sources. Through a reconstruction of the socio-political, intellectual, and textual history of the Shafi‘i school during its formative stage, my study identifies the factors that contributed to the emergence and success of the Shafi‘i paradigm; traces how this paradigm was propagated and re-interpreted, and from where it derived its authority; and explores the intimate connection between writing and thought in Islamic legal discourse. The book argues that the innovative legal hermeneutic of Muhammad b. Idris al-Shafi‘i (d. 820 C.E.), which enshrined normativity in a clearly demarcated canon of sacred sources, played a crucial role in the transformation of Islamic law from a diffuse oral tradition into a written legal science.