There are a few things you can do to break an enemy alliance in EU4. First, try to find out what their goals are and try to understand why they might want to work with another faction. If you can’t figure it out, talk to them and see if they’ll be willing to work with you instead. If they’re not willing, then it’s probably best to end the relationship. Another thing you can do is try to make your faction more popular by doing things like increasing trade or production bonuses for your faction. This will help make them more attractive to other factions and make them less likely to join an enemy alliance. Finally, always be aware of your surroundings and be prepared for any potential alliances that may form.
