This is something that really bugs me and I have not been able to find an answer for it. This pose is typically described as the Napoleonic pose but I realized many people before and after Napoleon, with different views, did it. Why?
There's one of Chopin posing with his friends of classmates from high school as well. It seems I can't find it on google but I have the picture somewhere on my HDD.
Oh and the last one I recall to make this pose is Stalin
So yeah, why do they all have a picture of them with their hand in hidden in their costume? It would seem weird if it's a trend because not many people did it (I guess) and it goes over a long period of time. Is it suppose to mean something?
Copying from a similar question a few months ago since there wasn't much discussion in that thread (hopefully there will be more here!)- How and why did the "hand-in-jacket" post become so popular in paintings and early photographs?
There is actually quite a good article on the topic- Re-dressing Classical Statuary: The Eighteenth-Century "Hand-in-Waistcoat" Portrait
The simplest answer is that it was a fashionable attitude. In portraits and photographs you have to find something to do with your hands, otherwise risk looking awkward. This particular pose has roots in the Classical period, something immensely popular during the 18th century. It not only became one of the standard poses for portraiture, but was even used casually. Hogarth's Marriage a la Mode #4, a satire and commentary on the state of fashionable marriage, shows the French Fop reclining in that attitude as well as the portrait of the English magistrate. It was considered a gentile position, though clearly mocked a bit for appearing pretentious. Men have a habit of hiding their hands in their pockets if unsure of what else to do with them, an awkward and slumped forward pose. This posture would have encouraged a better appearance of the body, whether in still pictures or day-to-day life.
Adding in that the reason it tends to be the right hand is that the more normal side for the buttonholes is on the left, so it will lap over the right. In the case of Mozart you can see how awkward it looks to try to do it the other way!
As a follow-on, almost all of them are sticking their right hand into their jacket, except for Mozart. Is there any significance to right hand vs left?