An Englishman locked in the castle, in 1474? Yes, Henry Tudor, duke of Richmond... the future Henry VII of England! Yeah, in England, at that time, the situation became pretty strained. We were in the middle of the famous War of the Roses, in the 15th c. Two Plantagenet sides, pretenders to the English throne, were fighting: the York and the Lancaster.
What about Henry? He was the last member of the Lancaster family. And he had no rights on the English crown… It was the ultimate battle of Tewkesbury between Lancaster and York: these one won. So, king Edward IV came to the throne! And Henry had to run away in France, in Brittany. He spent 14 years in Suscinio castle and in Vannes.
And when Edward died, his brother (Richard III) ascended to the throne, in 1483. Whoa, in fact, Richard usurped the crown by killing his 2 nephews (prince of Wales and duke of York) locked in London tower… A horrible crime which didn’t win unanimous support among lords, who decided to find another leader: they found it with Henry Tudor, the last Lancaster. But Henry took shelter in France… since 1470. Since, in fact, Edward IV’s takeover.
The young Tudor asked duke of Brittany François II to shelter him. François wanted to help Henry. And maybe marry him with his own daughter, Anne, the famous duchess? In fact, François dreamt about an alliance with England in order to counter the power of French kingdom… Well, that was the end of that! And in London, Richard III asked for Henry. But not for the same reasons.
To lock Henry in jail, of course! To put aside a rival. But François II didn’t want to hand over Henry. Hey, just look at what Richard did to ascend to the throne… François only promised the king to lock him. So, he left his host to the marshal de Rieux, who put Henry in jail in Largoët, from 1474 to 1476. Finally, Henry became king of England under the name of Henry VII and founded the Tudor dynasty in 1485, at the age of 28!