Duke of Medinaceli is an hereditary title in the peerage of Spain, accompanied by the dignity of Grandee. The Catholic Monarchs, Ferdinand II of Aragon and Isabella I of Castile, created the title and awarded it on 31 October 1479 to Luis de la Cerda y de la Vega. He also held the title of 5th Count of Medinaceli, which was first awarded in 1368 to his ancestor, Bernal de Foix.

Nicolás Fernández de Córdoba y de la Cerda, 10th Duke of Medinaceli, GE was a Spanish aristocrat. He was the 10th Duke of Medinaceli, an Ambassador of the King of Spain, Majordomo and Stable master of the queen, and a knight of the Order of the Golden Fleece.