The Muhammad Avatāra: Salvation History, Translation, and the Making of Bengali Islam reveals the powerful role of vernacular translation in the Islamization of Bengal. Its focus is on the magnificent seventeenth-century Nabīvaṃśa of Saiyad Sultān, who lived in Arakanese-controlled Chittagong. Drawing upon the Arabo-Persian Tales of the Prophets genre, the Nabīvaṃśa (“Lineage of the Prophet”) retells the life of the Prophet Muhammad for the first time to Bengalis in their mother-tongue. This book delineates the challenges faced by the author in articulating the pre-eminence of Islam and its Arabian prophet in a land where multiple religious affiliations were common, and when Gauṛīya Vaiṣṇava missionary activity was at its zenith. Sultān played a pioneering role in setting into motion various lexical, literary, performative, theological, and, ultimately, ideological processes that led to the establishment of a distinctively Bengali Islam in east Bengal. At the heart of this transformation lay the persuasiveness of translation on a new Islamic frontier. The Nabīvaṃśa not only kindled a veritable translation movement of Arabo-Persian Islamic literature into Bangla, but established the grammar of creative translation that was to become canonical for this regional tradition. This text-critical study lays bare the sophisticated strategies of translation used by a prominent early modern Muslim Bengali intellectual to invite others to his faith.