The Dentons are loosely based on real relatives of Jeremy Dyson, who went to stay with his relatives who told him to make himself at home, but found himself breaking lots of rules that he didn't know existed.
While saying her marriage vows, Barbara gets David's first names the wrong way around (she says "Charles David" instead of "David Charles"). This is a reference to Lady Diana Spencer getting Prince Charles' names wrong during their real-life wedding (Diana said "Philip Charles Arthur George" instead of "Charles Philip Arthur George").
Papa Lazarou is inspired by a landlord, of the same name, that the writers had when they were sharing a flat, who would frequently phone them up and ask to speak to Steve Pemberton. He would continue saying "Hello, Steve," "Is Steve there?". The League soon changed the name to Dave.
In the original BBC Radio 4 series, the name of the town was "Spent", most of the sketches were spread across the first two television series and there were unique answerphone messages from a Papa Lazarou-like character.
During the Christmas Special, Herr Lips' segment is obviously based off Dracula, however the following segment, involving a relative of Dr Chinnery involves a segment where the man he is staying with says "All my doors are open to you, except those which are closed" which is a direct reference to the original Dracula novel.