 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.