* Although a work of fiction, several characters in 'Kidnapped' are actual historical figures, including Alan Breck Stewart, who lived from 1711 to 1791.
* The murder of Colin Roy Campbell, which is a pivotal event in the novel, actually occurred, and Alan Breck Stewart was a suspect in it. Stevenson was inspired to write 'Kidnapped' by reading Sir Walter Scott's 'Rob Roy', which includes a description of Campbell's murder.
* Robert Louis Stevenson wrote a sequel- much less well known- to 'Kidnapped', called 'Catriona'.
* There have been several film versions of 'Kidnapped'. The only one I have seen is the 1960 Disney movie, starring James MacArthur as David and Peter Finch as Alan Breck Stewart. It's actually quite good, and sticks pretty closely to the book.