Our purpose is to study the limits between reality and fiction in the central chapters of the story of the foundation of the convento de la Encarnación of Lima by Father Antonio de la Calancha. The convent was founded in 1556 by Leonor de Portocarrero and her daughter Doña Mencía de Sosa, widow of the crown's traitor Francisco Hernández Girón. Despite the fact that the chronicles are consider a hybrid genre between literature and history by contemporary critics, Father Calancha's story is basically historic as it follows the model of humanist histography of the XVI century. We discuss that in this model aesthetic values are functional to the interpretation.