Factual error: The town in which a large part of the movie is shot is supposed to be Wismar, Germany. However the architecture of the town shows it's in The Netherlands. Delft, to be exact.
Suggested correction: Delft was used as a location, but the town square is not all that different from what an early modern North German city would look like. You can spot it if you know the place, but that applies to so many movies. In itself this is not a mistake, unless there were something that really betrayed it.