So I meet Pariden on this map, very first turn she greets me with a "warm welcome." I go straight to diplomacy that turn and spend ~500 gold on trade and economic treaties and a NAP. Hit end turn. "Your transgressions can not be forgiven, we are at war."

I imagine there's a second bug in there somewhere dealing with a "neutral" AI declaring war on me the turn after they meet me, which probably shouldn't happen. This is on normal difficulty.

I didn't know 1.12 was out until I came here to report this, but I saw nothing in the notes related to diplomacy so I'm guessing it wasn't fixed.