cartoon with time travel, mice and a lion prince

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I used to watch it with my son about five years ago, but I think it probably wasn't new then. A professor and his assistant (both mice) traveled back in time to the middle ages. They met a lion prince and some kind of evil witch/sorceress, who might have been a snake. The professor-mouse always had his hat on, and it was usually shown a little above his head, bouncing as he walked. For some reason I think the original language might have been french. Thanks in advance

ETA Found! by manow2 it's Argai