 FACT: In this movie, the Saxons are invading from the North, in  actual historical fact, the Saxons invaded from the South, as the  first Saxon Kingdoms in Britain were in Kent. Also, at the  beginning, the Saxons were actually invited in to help defend  against raiders from the North sea, later known as the Vikings.  Also, the Battle of Baden hill did not occur until several centuries  after the Romans abandoned Britain, and Baden Hill is not just  behind Hadrians wall, but much farther South.