Katherine of Aragon married Arthur Prince of Wales in old St Paul's Cathedral today in 1501, when they were both just 15. Henry VII threw a grand wedding, with a service that lasted so long that refreshments were served, and Arthur and Katherine each had a small shielded enclosure with a commode.

Katherine was escorted by the groom's ten-year-old brother Prince Henry, who married Katherine himself eight years later. Henry annulled his marriage after more than twenty years on the grounds that Katherine and Arthur had consummated their relationship, although Katherine maintained that they had not.

I believe the marriage was consummated – both parties were reported as being fit and healthy, and there was no suggestion of problems until after Arthur's death. Henry’s witnesses included a servant who claimed Arthur had said 'I have been this night in the midst of Spain'. But the only true witness was Katherine, who had strong reasons to lie. This distinctly personal issue is one of the most vexed questions in Tudor history.

Here’s an extract from my description of the wedding in The Constant Princess, my novel of Katherine:

Catalina felt the congregation murmur around her feet as she went past them, high on the stage that King Henry had ordered to be built so that everyone should see the flower of Spain meet the rosebush of England. The prince turned as she came towards him, but was blinded for a moment by irritation at the sight of his brother, leading the princess as if he himself were the bridegroom, glancing around as he walked, acknowledging the doffing of caps and the whispering of curtseys with his smug little smile, as if it were him that everyone had come to see.

Then they were both at Arthur’s side and Harry had to step back, however reluctantly, as the princess and prince faced the archbishop together and kneeled together on the specially embroidered white taffeta cushions.

‘Never has a couple been more married,’ King Henry thought sourly, standing in the royal pew with his wife and his mother. ‘Her parents trusted me no further than they would a snake, and my view of her father has always been that of a half-Moor huckster. Nine times they have been betrothed. This will be a marriage that nothing can break. Her father cannot wriggle from it, whatever second thoughts he has. 

Images: Portrait of an Infanta. Catherine of Aragon (?) by Juan de Flandes c.1496, Museo Thyssen-Bornemisza, Madrid; Arthur, Prince of Wales c.1500, Hever Castle