There should be better documentation about the alliances and star bases in my opinion. As they are, they leave to many things untold. I have been wondering this aswell.

I allied with 2 in one game.
The situation was this:

4 other races plust me, Alterians, Yor, Krox, and Drath.

I got into a long war with the Krox and they finally surrendered and gave thier planets to the Yor. Then the Alterians, who controlled at least 50% of the map, attacked the Yor. Since a lot of my planets were in Alterian Territory, or close to it, instead of attacking the Alterians I made Counter-alterian ships and gifted them all the the Yor. After 1 or 2 turns of pretty much being the United States in the beginning of WWII I was WARM with both the Yor and Drath and was able to ally with them just straight up with no other barganing chips.

Didnt help though we all got crushed haha.

I'm not sure you can allied if you are at war or the other party is at war. And I have been able to ally only with civ that are close to me, in normal diff.
Strange thing I hade: I made an alliance with the Yor, Drengin and Arcean (all allied to me), the Drengin attacked the Alterians and ask for the alliance to be honored, wich I did (I was loooking in a way to attack them anyway) but the then the other 2 didn't went to war, the alliance was still valid but looks like they weren't asked to honor my alliance (maybe a bug?).

I'm not sure you can allied if you are at war or the other party is at war. And I have been able to ally only with civ that are close to me, in normal diff. Strange thing I hade: I made an alliance with the Yor, Drengin and Arcean (all allied to me), the Drengin attacked the Alterians and ask for the alliance to be honored, wich I did (I was loooking in a way to attack them anyway) but the then the other 2 didn't went to war, the alliance was still valid but looks like they weren't asked to honor my alliance (maybe a bug?).

Nope thats the new alliance system. You don't have to honor the alliance when one teammate ATTACK another Civ. Only when one of the allied nations will be attacked you have to join the war against the aggressor.

Usually, you cannot bribe your way into close relations, unless your bribe is something damn substantial, like a whole step up the technology tree. For example I was to give you photon one and two while you are only at harpoon two and three for technology. This will only help if they are in desperate need or feel they are in desperate need due to a perceived threat from you or other nations. Here are some tips that may help.

1) Make sure all of your troop transports are... grounded. Built but grounded, even in "your" space (remember no one owns space and your rule for game purporses ends at the end or your planets atmospheres).

2) Dedicated more than 50% of your existing trade to that race, even if you take a hit finanicially. If your trading with their enemy, you will take a hit on relationship, not huge but enough.

3) Provide them with what they need, not what you can spare. Want to get rid of some old 1st generation ships... don't bother. The aliens don't want them either, although you don't want to give them your State of the Art ships, your back ground ships should do fine. If you don't charge some small pittance for them though they will think your brown nosing and I am not sure if that helps or hurts.

4) Kick some alien behind. Preferably their enemies. Nothing speaks bigger to aliens than you stomping out their enemies for them.

Hope that helps.

W/R
Suralle Straykat
Kat Lord @ Large