Most of the pictures of Napoleon on St Helena show him dressed in his little corporal's outfit standing or sitting on a picturesque headland gazing out to sea. I doubt he ever actually struck that pose ( he wanted respect not pity) but it's an affecting image and there are many, many versions, quite a few of them by British artists because the British love Napoleon. Even Turner had a go- though he varied the formula by having the Emperor with his back to a blazing sunset, gazing at an anemone in a rock pool.
He wanted his captors to address him as Majesty and they wouldn't, but was happy for 13 year-old Betsy Balcombe to call him Boney.
The picture I like best is by Horace Vernet. His Napoleon is doing the gazing out to sea thing but has changed his uniform for a baggy white suit and straw hat and is sitting on a rustic bench with a newspaper under his elbow. It won't have been done from life but I imagine it's the truest.