For things that canon changed about Muggle history, try Wikia:Mistakes in the Harry Potter books. (Most of that is irrelevant continuity errors, but some of that is contradictions with the real world.) Also see remarks about calendars in the HP Lexicon timeline.
For things that canon changed about Muggle history, try Wikia:Mistakes in the Harry Potter books. (Most of that is irrelevant continuity errors, but some of that is contradictions with the real world.) Also see remarks about calendars in the HP Lexicon timeline.