The film's action takes place during the reign of King Louis XIII of France (1610-1643), but there is a mention of the Rhine Confederation (founded 1806).
The puppy dog of Isabelle as child is white with a large black mark on the left ear. Some 15 years later, the dog "recognizes" her, but a few black marks are spread on the fur and the snout, and the large black mark has "moved" to around the dog's left eye - denouncing that two different dogs were used.