The traditional account of the Prophet Muhammad’s ascension has inspired generations of writers and storytellers from the beginnings of Islam until today. By the tenth century, narratives describing Muhammad’s encounter with prophets and angels, his colloquy with God, and his visits of heaven and hell lead to the formation of the "Book of Ascension," a novelizing and engaging literary genre most commonly written in Arabic and Seljuk Turkic. This is the study of an extremely rare Persian "Book of Ascension," which was written in Persian by an anonymous author and dates from the Ilkhanid Period (1256-1353). Christiane Gruber presents an English translation alongside the original manuscript text, together with critical commentary. The text appears to promote adherence, as well as to encourage conversion, to Sunni Islam -- providing a fascinating insight into the interplay between artistic practices and missionary efforts aimed at promoting Sunni Islam in Persian lands during Ilkhanid rule.