The fall of Constantinople in May 1453 created apocalyptic apprehensions and expectations that spanned the whole Eurasian continent. The Muslim conquest of the city was seen, in various Abrahamic apocalyptic traditions, as one of the portents of the End Time. The manifestation of this particular portent had considerable impact on Ahmed Bican, a mystic and litterateur who lived in Gallipoli. Ahmed resorted to divination, the science of letters and numerology to determine the nature and characteristics of the events leading up to the impending Day of Judgment. More importantly, he believed that the Ottoman enterprise was located in the middle of the tribulations preceding the End Time. He went so far as to attribute a near-messianic role to the Ottoman sultan Mehmed II. Ahmed predicted that Mehmed was poised to conquer Rome and repel the attacks of the Blond Peoples, the apocalyptic enemy par excellence of the Muslim community. Ahmed's projections and predictions are important for a variety of reasons. First of all, his work is an interesting representative of the post-classical Muslim apocalyptic tradition, a tradition that has not yet received the attention it deserves. Next, Ahmed's writings signify the emergence of an Ottoman apocalyptic tradition expressed in the Turkish vernacular. Also, Ahmed's portrayal of the Ottoman sultan Mehmed II indicates that messianism was already beginning to filter into the ideology of Ottoman imperialism around the middle of the fifteenth century, even though it would reach its full-fledged from only in the first decades of the sixteenth. Finally, Ahmed's works reflect the characteristics and preoccupations of many other treatises that were produced in the Muslim world in the fifteenth century. (He was educated in Cairo, and probably knew 'Abd al-Rahman Bistami, whose work he often cites as a major influence.) Very much like his counterparts in other parts of the Muslim world, Ahmed, motivated by a belief that the end was near, sought to uncover the true meaning of history. While doing this, he endowed Ottoman history with an unprecedented level of universality and described the Ottoman sultan as an actor in the cosmic battle between good and evil.