Duarte Fernando Álvarez de Toledo Portugal (c.1620 – 25 June 1671) was a Spanish nobleman, military and statesman, Grandee of Spain, 7th Count of Oropesa, 6th Count of Deleytosa, 3rd Marquis of Frechilla and Villarramiel, 3rd Marquis of Jarandilla, knight of the Order of Alcántara, who served as Viceroy of Navarre (1643–1645), of Valencia (1645–1650), of Sardinia, President of the Council of the Military Orders (1663–1669) and of the Council of Italy (1669–1671) and Spanish Ambassador to the Holy See.
He succeeded his elder brother, Juan Álvarez de Toledo Portugal, VI Count of Oropesa, who died as a child in 1621.
[1] From 3 November 1650, he briefly occupied the Viceroyalty of Sardinia, and in 1652 he was sent to Rome as Extraordinary ambassador to the Holy See.
His political career in Madrid under the reign of Charles II was crowned with the appointment in 1669 as President of the Council of Italy, and cut short by his death in 1671.
In 1636, Duarte married his first cousin Ana Mónica de Córdoba y Pimentel, 6th Countess of Alcaudete, with whom he had a son: