In the episode "Forward into the Past", Nick Knight wants a favour from Aristotle, the vampire who creates false identities for fellow members of the vampire community who need to move on. To persuade Aristotle to help him, Nick reminds him that he had saved him at the Battle of Hastings.
This is often cited as one of the most egregious mistakes made by a scriptwriter for the series. As the voiceover to the opening credits reminds the viewer every episode, Nick Knight was brought across in 1228. The historical Battle of Hastings, however, was fought in 1066. There is no way that Nick could have been there, either as a vampire or during his mortal life: the battle occurred years before he was born.
The Battle of Hastings took place on 14 October 1066 between the invading army of Duke William of Normandy (later and better known as "William the Conqueror") and the defending army led by Harold Godwinson, King of England. The battle took place at Senlac Hill, approximately six miles north-west of Hastings, which is a town in the south of England.
The battle was a decisive Norman victory, and Harold was killed. (Traditionally, it is believed he was shot through the eye with an arrow.) Although there was further English resistance, this battle is seen as the point at which William gained control of England.
The famous Bayeux Tapestry depicts the events before and during the battle. An abbey, known as Battle Abbey, was subsequently built on the site of the conflict.
- Historical information adapted from the Wikipedia article on the Battle of Hastings.
The following stories each, in one way or another, attempts to explain Nick's comment to Aristotle: