Duke of Arcos
He was the eldest son of 6 children of Antonio Alonso Pimentel, 6th Duke of Benavente, deceased 1633 and María Ponce de León, (1572–1618), daughter of Rodrigo Ponce de León, 3rd Duke of Arcos and the niece of the Duke of Arcos Rodrigo Ponce de León, 4th Duke of Arcos.