Coups are ridiculously common, and need turning down.
Last three games, almost every time an IG gets upset, if they have a commander of some sort a coup starts. I was playing as Austria and I genuinely had to deal with seven coups in about forty years.
It's literally like the moment a general gets a tiny bit upset he decides the solution is to overthrow the government. Shit, my latest game as the Dutch East Indies I had one overthrow the government for literally no reason. I was passing public schools! They didn't have an opinion on that! Apparently he stubbed his toe and decided to take it out on the country. And then when I gave the general the sack I wasn't even allowed to take the option to fight back, I was forced to let it happen.
Looking at the feed in the corner reveals the AI has this issue too.
Am I just horrendously misinformed? Were the 1800s actually a time of endless military overthrows in every nation on the planet?