 His successors were his illegitimate sons Leonello (1407–1450) and Borso (1413–1471), who was elevated to Duke of Modena and Reggio by Emperor Frederick III in 1452, receiving these duchies as imperial fiefs.In 1471, he received the duchy of Ferrara as papal fief from Pope Paul II, for which occasion splendid frescoes were executed at Palazzo Schifanoia.Borso was succeeded by a half-brother, Ercole (1431–1505), who was one of the most significant patrons of the arts in late 15th and early 16th century Italy.