This chapter examines genealogical documents in a particular modern context — that of Morocco, with particular emphasis on the village of Zawiyat Sidi 'Abdel'aziz ben Yeffu, where a manuscript of questionable authenticity known as al-jafriyya has played a key role in authenticating one lineage's genealogical claims. More specifically, it analyses the history, imaginary, and politics underlying the power of genealogy in Morocco in order to illustrate the seminal significance of prophetic descent in Moroccan political and religious practice and belief. It also considers the role of royal decrees, ẓāhirs, which confer and confirm economic and political privileges and are paired with an ‘arresting mythology’ that supports the image projected by members of the lineage.