Yea right now Sweden is the only one I have a decleration of friendship with so we're on good terms. I already took a city state though (Zanzibar as you can see in the screenshot) and the only one that seemed to care was Siam and only because he had pledged protection to them.
I usually don't recommend reloading turns as it is a crutch, but take this challenge (if you have the time/interest)
Kill of Siam and see how sweden + rest of the world reacts. It may not be immediate, but I'll be interested to see if they don't renew or DoF or add 'you're a warmongering menace' in your diplo screen.
In anycase, back to the main game. Let them take it, or keep Siam alive as a buffer between you and Sweden.
EDIT: Actually I believe Sweden is also currently at war with Siam. Wouldn't it be a little bipolar of him to get mad at me for wiping out a mutual enemy?
Why would it be? Your 'common foe' modifier will outweight your Civ elimination penalty in the near term, but over the long term, they will know you killed off Siam and will count it against you. Plus if you grew fat from the war, some AI will treat that as a threat, because not only if the elimination penalty weighing on you, you also have your score changing and the AI very much do look at scores to figure out who their next threat it. They may not look at it like humans do, but if you play through enough games, you'll notice they act very predictably accross many games and there's very definately 'score' competition among the top civs.
This is why in cases of joint wars where 2 or more civs including yourself dismember another Civ, its best not to be the one to eliminate. Because you are already getting hit some a warmonger penalty with each city you take, mild but it adds up over many cities. You get hit with another penalty with taking a capital (conquest VC flag), and a third penalty for killing off the Civ.
