[Alneyan]

All effects in the happiness file are one-shot, except the last few lines where it should be per turn (natural decrease and penalty for other races). Colonising a lot of stuff on the same turn will give you a high happiness increase, while multiple glassed planets on the same turn will destroy your happiness.

The happiness penalty for treaties is also one-shot, which can lead to some peculiar game mechanics. If you are peaceful, you can be *very* happy indeed by signing trade treaties followed by trade & research followed by military alliance followed by partnership or back to trade & research, followed by yet another beneficial treaty... It might even work if you sign the same treaty over and over, though I haven't checked that. Don't ask.

Bloodthirsty is decent at least, since riot runs have a lower impact against them. They won't go up to Jubilant on their own, though, unlike Peaceful races (where colonies and treaties are normally all it takes). Sign all your treaties on the same turn, if possible, if you want to minimise the happiness hit. The whole system doesn't make much sense at all.

While speaking about happiness, keep in mind that the Happiness characteristic is utterly worthless in the stock game. The positive effect is negated by the natural decrease, and the negative effect is negated by the same thing ("natural decrease" really is "natural move towards neutral"). If memory serves, your happiness will slowly go down on its own from -55% to happiness or so, and the decrease isn't particularly harsh even then.