cool question, and I'm always happy to have a reason to think about Napoleon (despite the evils he inflicted during his rule)-- but in Googling this question myself, it looks like someone already covered it in /r/AskHistorians ! https://www.reddit.com/r/AskHistorians/comments/1ra1oe/why_was_napoleon_exiled_and_not_executed/ (credit to /u/LordSariel )