This collection contains a selection of primary, mainly Russian archive documents on the affair of the famous Naqshbandi Khalidi Sufi master Zayn-Allah Rasulev (1833-1917), the founder of an important khanaqah and madrasa in Troitsk in the Eastern Ural region. The documents deal mainly with the repression implemented by Russia’s police against him in the 1870s, and with his two successive exiles to Vologda and Kostroma. In his long and substantial historical introduction on the life and deeds of Shaykh Zayn-Allah, the Editor unintentionally underlines the difficulty to classify him as an innovator or as a traditionalist. He also stresses the significance of Shaykh Zayn-Allah’s revenues (notably through collections of sadaqat during annual celebrations of the mawlid al-nabi) for the rise of the shaykh’s influence, and of the jealousy of less successful Sufis and registered mullahs. From this viewpoint, the set of documents edited in the present volume also confirms the central role played by the Muslim Spiritual Assembly in the shaykh’s fall and exiles. More generally, they shed light on the attitude of regional civil power and of Russia’s Ministry of the Interior on Sufism, and on “popular” practices of Islam in European Russia, in a time of intense conquest and colonisation in Central Asia. At the same time, they provide us with elements of information on the diversity of Sufi affiliations and practices in the Ural Region of Russia. They also offer information on concurrence and rivalry between varied types of religious personnel of Islam in the Russian Empire, notably between Sufi leaders and “registered” mullahs. So doing, they allow historians of Russia’s Islam to qualify the often simplistic dialectical approach and dichotomy between “reformists” and “traditionalists”.