I actually learned that in high school in the 1960’s. Louis Napoleon was the nephew of Napoleon Bonaparte. He was democratically elected as President of France (after the revolution which serves as the climax of Les Miserables), then eventually seized absolute power and declared himself Emperor Napoleon III. He was deposed after France lost the Franco-Prussian War.
NVM = Never Mind, according to Wikipedia. Or it could mean Non-Volatile Memory, which I suppose is one attribute of comic strips.