Exist any historical ground in this? :
It seems that a Spanish adventurer called "Juan de Lepe" wound up at the court of Henry VII in London some time around 1500 and became great friends of the king. One day they played a game of chess, with a dare that, if Juan were to win, he would be king for a day. He won. The 'King' promptly emptied as much of the royal loot as he could and, while this sounds unlikely, actually made it back to Lepe (Huelva) and on his death left his possessions to a local Franciscan monastery, the "Nuestra Señora de la Bella". A good story? It gets better.
The Royal Crown of Henry VII of England, part of the "booty", is on display for the first time in 400 years in the monastery. Sounds like it's worth a visit.
Link to the spanish article with photograph of the crown: