The concepts of center and periphery are not always mutually exclusive; one often resides within the other. This idea is central to my critical evaluations of three historical personages of fifteenth-century Castile: Enrique IV de Trastmara, doa Leonor Lpez de Crdoba, and Alfonso de Cartagena. Each of these figures had a central political function in the kingdom, yet each also lived a dual existence at the margins of Castilian court. In this dissertation, this duality is examined using a combination of historical sources and contemporary psychology. Certain nuances in the historiographical genre of the Castilian chronicle of the fifteenth century stand out as distinct from the chronicle of previous centuries. One of these is the liberal addition of personal commentary by the chroniclers themselves, breaking to a degree with the paradigm of unadorned, historical fact-telling. These personal and often politically charged opinions have significantly contributed to the polarization of modern interpretations of the events and people described in these histories. The incorporation of recent psychological research allows for new readings of the chronicles and new interpretations of the mysteries surrounding Enrique IV, Leonor Lpez, and Alfonso de Cartagena.