I tend to idealize the Middle Ages and the monarchies of Europe but the more I read about them, the more I realize that there was heavy injustice back then too.
Of course Catholicism should always be the state religion. But some of these kings were real cowpats. In the Thirty Years War, Catholic France took the side of the Protestants against Catholic Spain and the Holy Roman Emperor.
Of course if they didn't Spain would have eventually built up momentum and crushed France -- but is that really so bad? I think not. In Spain you work from 12-1 in the afternoon and then take a siesta until five. Then you have a leisurely meal and go to sleep. This is the way all peoples should live! It's obvious that Spain should rule the world. ( I will tell you, we can only be roused, like Don Quixote, for divine missions ).
But it is odd to think of Catholics killing Catholics all in the name of a king. What does moral theology say about such activity? I guess you just forgive your brother as he's ramming a halberd into your throat or pouring hot oil down your shanks. I know where I'd be -- in a monastery.
Michael