Late in life Nuño accompanied James on his military expeditions into Navarre and Valencia (conquered 1238). In 1220, Nuño had married Teresa López, daughter of Lope Díaz II de Haro, Lord of Biscay. They had no children, so his lands and titles escheated to the crown on his death, either late 1241 or early 1242. The troubadour Aimeric de Belenoi composed a "planh" on his death, significant of his reputation for courtliness and chivalry. He was buried in the hospital of Bajoles, near Perpignan, now disappeared. He left an illegitimate son, the "Bastard of Roussillon," who defended the city of Elne from the French during Aragonese Crusade in 1284.