First wife of Henry VIII and married to him for longer (1509 - 1533) than the other five put together. Unlike them she was a powerful royal in her own right. Daughter of Ferdinand and Isabella, born near Madrid, she came to England as a Spanish princess to marry Henry's elder brother, Arthur, but he was dead within 5 months of the wedding. The two 15-year-olds had not managed to conceive (a queen's main function) so what to do with her, that did not involve losing the valuable connection with Spain, nor returning her dowry?
Her miserable 7 years as Arthur's widow, with an uncertain future and little money, brought on anorexia, which may partially explain many failed pregnancies that followed. There was a suggestion that she could marry her father-in-law, Henry VII, but marriage to her brother-in-law was chosen. For the Pope to allow this Catherine had to declare that her marriage to Arthur had never been consummated and was thus null and void. All well and good, but when Henry wanted rid of Catherine to make way for Anne Boleyn, his grounds for divorce rested on his assertion that she had lied then and so his marriage to Catherine should be annulled. The site of the preliminary meetings where this divorce was discussed with the papal delegation seems to be in dispute: Black Friars and/or Bridewell Palace. Henry got his way and Catherine ended up with the title "Dowager, Princess of Wales", i.e. Arthur's widow. Died Kimbolton Castle.
She produced one daughter, who later become Queen Mary I.
In 1507 she was the Spanish Ambassador to England, the first female ambassador in European history. In 1513 while Henry was off fighting the French she was Governor of the Realm and Captain General of the King's Force, with which titles she waged war on Scotland, addressing the army and wearing full armour.