I'm pretty new to Sins.

I'm playing the original game without the two expansion packs.

Playing single player.

In my first few games I got the victory screen when my opponents were all eliminated / almost eliminated, which is fine.

Later I won a couple of larger games when everyone other than my ally was eliminated / almost eliminated, which is also fine.

So now I am playing a very large map, and everyone is eliminated (there was a race eliminated message and the diplomacy screens show cracked glass over the portrait) except 3 races which I am full allies with (all treaties, 100% opinion). But the game hasn't finished...

So, what do I have to do to win now? Do I have to attack one or more of my allies? Does it make a difference that my allies are not all allied with each other?