SPOILERS!
Duc de Grenouille is frustrating me...
Bretonnians do not have dukes other than the rulers of dukedoms (at least not according to KotG). Grenouille is French for a frog. So does this mean he's actually a noble spy from Mousillon? Or a spy for the king? Or what the hell could this mean? There is no location called Grenouille anywhere. Argh.