Our ancestor François was Seigneur de Castelnaud. What that means is he was basically the landlord on behalf of the king.
When the cream of the crop left France they left behind their castles. Château de Castelnau was one of ours. It fell into disrepair & was eventually bought by a man who fixed it up then left it to the state when he passed. Now it’s been converted into a medieval war museum.
Check out this site for more info.