
Originally Posted by
Rebun
I used to feel that there was hardly any control over friendships and that whether an AI hated you was situational based on whether or not you were next to them. That was until i played a emperor continents game where i was able to keep at peace a runaway civ on my borders, and even complete a space victory without them caring. Since then I've started to learn a lot more about the diplomacy AI and how to cement friendships and avoid being DoW'd by your friends. Heres what I've found:
1. The Diplomacy Overview -> Global Politics view is key, it will tell you who has denounced who, who have become friends and who is at war with whom.
2. To make a solid friendship, get someone to accept or request a declaration of friendship early on. From that point, keep an eye on them in the global politics screen, if they make friends with anyone else, see if you can make friends with this third party. The AI seems far less likely to betray you if there is a 3rd party in your makeshift alliance. After that, i'm usually able to refresh both AI's declaration of friendships indefinitely if they themselves remain friends (which they usually do because there both friends with you).
3. When your allies have denounced some other AI, you can seize this opportunity and denounce that same leader as well (unless they are a threat to you), this will further boost your relations and give you the 'We have denounced the same leaders' relations boost. But in doing this you may be setting up a long-term enemy.
4. Be careful when you've made yourself an alliance and an external AI wants a declaration of friendship, i usually refuse these offers and check the global politics screen to see if they've denounced or at war with any of my allies. If not, i consider befriending them later.
5. Trade luxs/research agreements to your allies, this will also make them more hesitant to betray you.
Its still very important to have a military though, the AI looks down on civs that have a poor military and become more likely to attack. Its also important because you will undoubtedly make some enemies in your game and will probably be involved in combat at some stage. The upside to this strategy i find is that it allows you some control over who you want to be your long-term friends, which can even include your direct neighbours.