A little known ( unfinished ) book by Robert Louis Stevenson called St Ives tells the adventures of a french hussar captured by the british and held in Edinburgh castle, Scotland.
The book has been made into a film twice, the latest being, St Ives, All for Love made in 1998 and released in 2000.

St Ives, All for Love - the plot:

Jacques St. Ives (Jean Marc Barr) is a much-envied officer in Napoleon's army who requests a demotion in rank so as to avoid a number of duels from fellow officers, who may challenge only those of an equal rank. To his shock, Jacques is demoted to the rank of private by a furious commander and is sent to the front where, through a mishap, he is taken prisoner and sent to Scotland where the prison warden is a bored British officer, Major Farquar Chevening (Richard E. Grant). The major lusts for a local lovely, Flora (Anna Friel), but she lusts for Jacques; Flora's randy aunt Susan has eyes for the major, while Flora arranges an escape for Jacques with his long-lost grandfather, and the major takes lessons in womanizing from Jacques. In a nasty turn, St. Ives' bitter and violent brother (Jason Isaacs) plots to kill Jacques before he can assume their grandfather's inheritance.

Before that the 1949 film, The Secret of St Ives was produced:

Long before he became a highly respected Wall Street financial adviser, Richard Ney was a minor-league film star. In Secret of St. Ives, Ney plays Anatole de Keroual, the unofficial head of a group of French prisoners during the Napoleonic Wars. Organizing an escape from his British captors, Anatole leads his fellow prisoners to Scotland, thence to London. Doggedly pursued by nasty British major Chevenish (Henry Daniell), Anatole is recaptured and sentenced to hang. How he wriggles out of this dilemma is the dramatic thrust of the film's last reel. Vanessa Brown co-stars as Floria, Anatole's British sweetheart. The Secret of St. Ives was adapted from a novel by Robert Louis Stevenson.

As luck would have it the 1998 film, St Ives, All for Love is on Youtube. Might be of interest to Caroline ?