The twelfth century saw what has been acknowledged by historians as a change in the nature of Byzantine emperorship with the reign of Alexius I Comnenus (1081-1118) and his succeeding dynasty. The rule of the Comneni has been associated with an emphasis on military achievement and a greater dynastic focus. While the practical changes to imperial rule under the Comneni have been well documented by historians, a focus on the character of the emperor and his depiction in historical writing has not yet received scholarly attention. The reign of Alexius was documented by two twelfth-century historians, Anna Comnena and John Zonaras. Their works offer two markedly different interpretations of Alexius's character and his suitability to occupy the imperial office. Anna Comnena's Alexiad draws on Biblical and Classical traditions to establish Alexius as the model of an ideal emperor. John Zonaras's Epitome Historiarum sets different standards for private men and for emperors. While Alexius's character is sufficiently virtuous for a private man, he falls short of the standard imposed for an emperor. This research shows that both writers create an ideal of emperorship in which the character of the emperor plays a vital role. The nature of this ideal, and the influences that inform it, are unique to each writer. Anna and John identify similar character traits in Alexius. Their point of difference, however, is whether they believe Alexius's character is suitable for the imperial office, and the extent to which he fulfils their ideal standard of emperorship.