Diego de San Pedro (c. 1437 – c. 1498) was a Castilian writer about whom no one knows very much other than what he says in his works. Scholars also rely on what they infer from the context in which he wrote them and the many nobles to whom he has been linked.
According to San Pedro's prologues in Tractado de amores de Arnalte y Lucenda (The Love Between Arnalte and Lucenda), Cárcel de amor (The Prison of Love), and Desprecio de la Fortuna (The Disdain of Fortune), San Pedro could not have written before 1470.
The Tractado de amores de Arnalte y Lucenda is dedicated to Queen Isabel’s ladies-in-waiting and to the queen herself. Its second edition describes San Pedro as a servant of Don Juan Téllez-Girón, Count of Urueña. Don Juan was powerful, because he was the half brother of Isabel and was favored by King Enrique IV of Castile. San Pedro dedicated Desprecio de la Fortuna to him, calls him “his lord,” and says that he was in his service for 29 years. San Pedro dedicates Cárcel de Amor to Diego Fernández de Córdoba. Diego Fernández was also related to the Téllez-Girón family, because he married Juana Pacheco, a niece of the count. He was 'alcaide de los donceles', or the leader of a light-cavalry troop of privileged young men who served as the king’s bodyguard. San Pedro also mentions Doña Marina Manuel, a member of the highest Castilian nobility, in this prologue.
Carmen Parrilla assumes that San Pedro was a grown man by the end of the 15th century, when he wrote Desprecio de la Fortuna, because he apologized for the mistakes of his youth in this work. Parrilla has found that San Pedro was writing in the 1480s and 1490s for the queen’s entourage. He probably died and went unnoticed by the younger people who were unfamiliar with him.
According to Keith Whinnom, San Pedro must not have been a major literary figure of Queen Isabel’s court. Indeed, San Pedro expresses fear of the women’s mockery in his dedication to the ladies in Tractado de amores de Arnalte y Lucenda. Whinnom describes San Pedro as an hidalgo, or a member of the lower nobility, who did as he was ordered, seemed afraid of ridicule, and was willing to go to extreme lengths to please the ladies-in-waiting of the queen.
Lastly, it is unclear if Diego de San Pedro was a converso (converted Jew or Muslim) or if he was not. It was common for those who converted to Christianity to use a saint’s name as the family names. However, Whinnom points out that both old and new Christians followed this practice. San Pedro’s professions as secretary to the Count of Urueña could also indicate that he was a Jewish converso, but there is no extant evidence of this fact. Several scholars point to the tone of some of San Pedro’s works in support the theory, and maintain that Cárcel del amor is a literary response to the initiation of the Inquisition, but all this is mere speculation.