“This is a whale of a book, not only because of its size. Its geographical and chronological scope are vast, and it combines great philological skill with considerable conceptual sophistication. . . . This is a profound and important book whose arguments and conclusions are on the whole convincing. This is truly a groundbreaking study and as such can be recommended to a wide audience.” —International Journal of Middle East Studies “This is an epic book. With it, DeWeese has opened up whole new vistas onto the religious landscape of the Mongol empire and post–Chingizid Inner Asia. Charting territory almost entirely unknown to most students of Islamic history, and particularly those unfamiliar with Russian scholarship in this area, DeWeese pulls together material from a wide range of sources and disciplines, and in the process conjures up tempting paths to explore and many riches still to be unearthed.” —Royal Asiatic Society “This is an original and distinctive contribution to the fields of history of religions, Central Asian studies, and Islamic studies. There are no comparable studies. It comes at a time when Central Asian studies after years of relative obscurity is now very much in the limelight. The issue of Islam and its relationship to ethnicity and nationalism is of central significance. DeWeese demonstrates a command of the body of relevant sources and in fact adds to it significantly. There is a mine of new information accompanied by a fine summary of the state of the art. The combination of the author's methodology, materials, and quality of analysis has produced a study that is distinctive in extending the frontiers of scholarship.” —John L. Esposito, Georgetown University