Duke of Medina Sidonia is a peerage grandee title of Spain in Medina-Sidonia, holding the oldest extant dukedom in the kingdom, first awarded by King John I of Castile in 1380. They were once the most prominent magnate family of the Andalusian region, the best-known of whom, Don Alonso Pérez de Guzmán y Sotomayor, 7th Duke of Medina Sidonia, commanded the Spanish Armada at the end of the 16th century. The defeat at the hands of weather and the English in 1588 brought disgrace to this family. The House of Medina Sidonia traces its descent from Alonso Pérez de Guzmán.
The facade of the palace of the Duke of Medina-Sidonia
Grandee is an official aristocratic title conferred on some Spanish nobility. Holders of this dignity enjoyed similar privileges to those of the peerage of France during the Ancien Régime, though in neither country did they have the significant constitutional political role the House of Lords gave to the Peerage of England, of Great Britain and of the United Kingdom. A "Grandee of Spain" nonetheless enjoyed greater social privileges than those of other similar European dignities.
Equestrian portrait of Isabella II, her husband Francis, King Consort of Spain (left), and Infante Francisco de Paula (right) with the most important Spanish statesmen and army officers of the time, many of whom were Grandees of Spain, by Charles Porion, 1862
