This dissertation examines how monarchs of eleventh- and early twelfth-century León (Fernando I, Alfonso VI, and Urraca) used religious language to construct their vision of royal power. The primary sources studied are royal charters. Often much of language (especially religious language) used in charters is dismissed by historians as merely formulaic, but this study demonstrates that the monarchs, along with their advisors and scribes, carefully and intentionally chose, from a wide range of possibilities, language that suited their concerns and policies.

This study also shows how the charters were issued: in court, read aloud and understood by the audience; and also in a liturgical manner that lent sacrality to the event, mixing religious and royal power. The church played a great role in the production and preservation of the charters, yet always in concert with the monarch. The monarchy was an institution important to both cloister and court, and the construction of kingship was clearly a collective enterprise. This is no more evident than in the case of certain forgeries that support ideas of kingship just as much as the documents originating in the royal court do.

There are two related contributions to the understanding of medieval history in this dissertation. One is methodological: it shows that the language of the charters is intentional and sophisticated, and that by taking the language seriously, we open up new possibilities for their study. The second follows the first: the reading of the Leonese royal charters using this method sheds new light on the concerns and policies of the three monarchs. The charters display a continuing interest in the creation of sacred space, either through the translation of saintly relics or the patronage of new religious institutions such as the monastery of Cluny. The monarchs also used the charters to address conflict: in the case of Fernando I, the questions about legitimacy surrounding his accession to the throne; in that of Alfonso VI, the creation of a new idea of a Muslim enemy; and in that of Urraca, the difficulties raised by the rare situation of a woman ruling in her own right as queen.