Juana, known as Juana the Mad ('La Loca') 1479-1555
Countess of Flanders and Queen of Castile

The daughter of Ferdinand, the Catholic, and Isabella of Spain, she was born in Toledo, and married Philip I, the Handsome, of Flanders (1495). The couple settled in Ghent, and had several children, of whom the eldest was the future Holy Roman Emperor, Charles V. On her mother's death (1505), she became Queen of Castile. She and Philip moved to Spain in 1506, the year Philip died, and Juana, who suffered from severe depression which had been aggravated by her husband's infidelities, was declared unfit to govern and was kept under close watch in Tordesillas, while her father became Regent of Castile. Although Ferdinand died in 1516, her son, Charles, by then King of Spain, did not release her and Juana remained incarcerated, along with her youngest daughter, Catalina, until her death.