This book investigates Muslim narratives on Qurʾanic distortion through a meticulous analysis of hadith. Using isnād-cum-matn analysis, Seyfeddin Kara discovers the historical origins of this disputed claim and illuminates the dynamic interplay between Sunni and Shiʿi traditionists. He demonstrates that isnād-cum-matn analysis is not only an important tool for dating hadiths but also crucial for uncovering forgeries. By identifying the individuals responsible, he provides new explanations of forgery culture in early Muslim society. Kara illuminates debates over the textual integrity and evolution of the written Qurʾanic text, offering insights into the enigmatic early history of Islam. By pushing the boundaries of isnād-cum-matn analysis, this book makes methodological advancements in the study of early Islamic history and contributes to its reconstruction on the question of the canonised Qur’an’s integrity.