The so-called Apocalypse of Samuel of Kalamoun is a Coptic text of uncertain date and authorship now preserved only in its Arabic translation. It contains the strongest denunciation of the language shift in the Middle Ages of Egypt, by which Coptic was replaced by Arabic. It records that the Christians in Egypt were becoming increasingly Arabized in culture and customs, although actual conversion to Islam does not seem to be a concern. The date of the text depends on the interpretation of the list of "predicted" Arab kings which it contains. These seem to be the Fatimid caliphs, and the work should therefore be dated to the crusader period. However it has been dated as early as the 8th century. The work of the author is supposedly the 7th century monk Samuel of Kalamoun. The text is edited with a French translation in an unsatisfactory edition by J. Ziadeh.