Throughout medieval history, the writings of court secretaries, chancellors and other scholar-officials sought to rationalize dynastic sovereignty and harmonize it with notions of religio-political legitimacy that were in currency. Political treatises, historical chronicles, and poetry were the primary means through which particular norms of sovereignty and visions of legitimate royal authority were communicated. The frequent exchanges (through the medium of epistles) among intellectual networks of scholar-ministers, the production of coinage and the construction of monumental inscriptions across the royal palaces, colleges and other structures became the channels for the dissemination of these ideas. This paper utilizes texts (both edited and unpublished manuscripts), numismatic and epigraphic evidence to examine the various strategies of royal legitimation employed within the Nasrid Kingdom of Granada (1238–1492), the last surviving Muslim kingdom in the Iberian Peninsula during the Middle Ages. It explores the emergence of new conceptions of royal and quasi-caliphal sovereignty, embodied by the ubiquity of the title “God’s caliph” (khal?fat all?h), in the writings of one particular intellectual-political network of Andalusi and North African secretaries, chancellors and statesmen during the 14th century. The usage of the caliphal title challenged the classical Islamic notion that sultans and emirs were invested with legitimate authority by a universal, symbolic caliph. Rather, kings, by virtue of their sovereign authority and kingship, were endowed with a divine mandate to rule and were effectively God’s representatives on earth. Within the context of the kingdom of Granada, the emphasis on caliphal authority was complemented by elaborate genealogical claims, which simultaneously connected the Nasrid dynasty to the Ansar of Medina and the pre-Islamic Himyarite kings of Arabia. While examining the relationship between these religio-political and genealogical bases of legitimation in the Nasrid context, this paper also interrogates similarities between these developments in the Islamic West and broader reconceptualizations of royal power and authority in the late medieval Middle East.