Born on 6/11/1479, Juana was the third child of Queen Isabel I of Castile and King Ferdinand V of Aragon.
In 1496, aged 16, Juana was betrothed to Philip of Flanders – a match designed to further strengthen and consolidate Habsburg power in the face of the growing French power and threat.
Juana never expected to inherit the throne but following the death of her mother and older siblings she became queen regnant of Spain in November 1504.
Her succession, however, meant that her father, Ferdinand, lost his title as king in Castile. Unwilling to lose his title, Ferdinand claimed that she was unwell and unfit to rule, had himself proclaimed her guardian and claimed that he himself was her co-regent. Philip, Juana’s husband, was also unwilling to forfeit his chances of ruling and made a similar claim to the Castilian throne. Juana, meanwhile, was confined by her husband in the Low Countries.
In 1506, Juana and Philip travelled to Castile, persuading Ferdinand to finally agree to retire to Aragon. When they met, the two men signed a treaty declaring that Juana was unfit to rule and must be excluded from government.
When Philip died just months later, a regency council was set up without Juana’s permission and when her father returned in 1507, he resumed his role as regent in a decree that Juana refused to sign. Once again, Juana was forced into confinement.
When Ferdinand died in1516, her son Charles – later the Holy Roman Emperor – took over the role as king and regent. Once again Juana was confined, this time in the now destroyed Royal Palace of Castile where she died, aged 75, in 1555.
To this day, historians and royal scholars dispute the validity of the mental health claims made against Juana by her father, husband, and son.
Antonio Benitez de Lugo, “Doña Juana la loca, más tiranizada que demente,” Revista de España, 100 (10 and 29 October 1885): 378-403, 536-71
Bethany Aram, Juana the Mad: Sovereignty and Dynasty in Renaissance Europe (Baltimore: John Hopkins University Press, 2005)
Ludwig Pfand, Juana la loca: su vida, su tiempo, su culpa. Trans Felipe Villaverde (Madrid: Espasa Calipe, 1943)
María Gómez, Santiago Juan-Navarro, and Phyllis Zatlin, eds., Juana of Castile: History and Myth of the Mad Queen (Lewisburg: Bucknell University Press, 2008).