We know that the last event to trigger the prophesy featured in the trailers was that "The sons of Skyrim would spill their own blood" or such. This civil war was the last straw in the line of events to come before the dragons could come back. Other than that, I think that's all we know about it, but I could easily have missed something.

I don't think the fact that this game is set in Skyrim and that the civil war happened in Skyrim is a coincidence. This is purely speculative of course, but how much do you think the civil war will effect the game?

We don't know how long ago the civil war was, but we do know that it happened within 200 years, because that is when Oblivion is set and the civil war happened between then and when Skyrim is set. How long ago do you think it happened?

If it happened closer to 200 years ago, it would probably have little effect on the game; but if it happened more recently, then it could be a profound plot element. Maybe factions still exist? I know the main point of the story is fighting back dragons, but could the Dovahkiin be trying to put Skyrim back together along with fending off dragons? Quite the heroic sort!

What do you think? How much will the civil war effect the game?

On a purely speculative note, what do you think the cause of the war was?

well what we know is the empire is falling apart and the king of skyrim was murdered.. so i guess its a war of succesion or people trying to use it to break free from the empire.. so either two people with claims to the throne or loyalist(empire supporters) or reformists (trying to put skyrim as its own sovereign nation)
i think the civil war is set to coincide with the setting of the game.. otherwise bethesda have missed a huge chance to have a great secondary main quest which would be as good dragon hunting could be..

EDIT: this is someting that intriqued me so i have got a similar thread alreayd up
http://www.gamesas.com/index.php?/topic/1170273-the-civil-war/

Hopefully a choice in the storyline. My guess is that the storyline will begin by focusing on the war, but the dragons arrive, and the game ends with some compromise between both sides to fight the mutual threat to survival, which makes the game end in a similar fashion regardless of your storyline choices. Good or bad? Well, I certainly don't want another Dragon Break situation (though now would make more sense than any other time...)

from what I know, the king of skyrim died and there were two sons, fighting for the throne, the civil war was linked to that