Juan Alfonso Pérez de Guzmán y de Guzmán-Zúñiga, 6th Duke of Medina Sidonia (24 March 1502—26 November 1558) was the son of Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia

Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia

Don Juan Alfonso Pérez de Guzmán y Afán de Ribera, 3rd Duke of Medina Sidonia inherited the title in 1492, aged 28. In 1502, as Gibraltar was transferred to the Crown, the Marquisate of Gibraltar disappeared....

, half brother of Enrique Pérez de Guzmán, 4th Duke of Medina Sidonia

Enrique Pérez de Guzmán, 4th Duke of Medina Sidonia

Don Enrique Pérez de Guzmán y Fernández de Velasco, 4th Duke of Medina Sidonia was the son of Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia. He was Duke of Medina Sidonia from 1507. No issue by his wife María Téllez Girón....

, and the brother of Alfonso Pérez de Guzmán, 5th Duke of Medina Sidonia

Alfonso Pérez de Guzmán, 5th Duke of Medina Sidonia

Alfonso Pérez de Guzmán y de Guzmán-Zúñiga, 5th Duke of Medina Sidonia was the son of Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia and became Duke of Medina Sidonia in 1512 when his half brother, Enrique Pérez de Guzmán, 4th Duke of Medina Sidonia died childless.Declared "impotent and...

. Upon his brother's death in 1549, he became Duke of Medina Sidonia.

He was the father, with Ana de Aragón, of Juan Claros de Guzman y Aragón, or Juan Carlos Pérez de Guzmán y Aragón (d. 1556), who married Leonor de Zúñiga y Sotomayor. However as Don Juan Carlos, predeceased his father in 1556, the title passed to his eldest son Alonso Pérez de Guzmán, 7th Duke of Medina Sidonia.