16 Royals Who Suffered From Hereditary Mutations And Defects Caused By Inbreeding

Joanna of Castile. Portrait by Juan de Flandes, c. 1500 / Wikipedia

2. Joanna of Castile Slept Beside Her Husband’s Corpse

Before Charles II, there was Joanna of Castile, the older sister of Catherine of Aragon. She was from the house of Trastamara, which had been engaging in cousin marriages for centuries. Her parents, King Ferdinand and Queen Isabella, were second cousins. The family’s long tradition of inbreeding may have been at least partially the reason why Catherine couldn’t bear any children. Joanna set the stage for her posterity to have their own challenges, as she married into the Habsburg line.

As a child, she was known to be intelligent, inquisitive, and somewhat moody. At age 16, she entered into an arranged marriage with the son of the Holy Roman Emperor (who was neither holy, nor Roman, nor an emperor), Philip the Handsome. Himself the product of inbreeding, he was known for being a philanderer, but Joanna was completely smitten with him.

When she ascended to the throne, due to the unpredicted deaths of her older siblings, she had a full mental breakdown, exacerbated by Philip’s behavior towards her. When she found one of his mistresses, she stabbed her in the face. Still, she remained madly in love with her husband. When he died unexpectedly, she held onto his corpse and slept beside it every night.

History remembers her as Juana la Loca, Joanna the Crazy.

Age: 76 (1479-1555)
Birthplace: Toledo, Spain