Stormcloaks Or Empire (One Of The Three Certainties Of Life)

[GloatingSwine]

The armies of High Rock and Skyrim are the Imperial Legion and they were fighting in Cyrodiil! We're flat out told as much in game! Thats where Ulfric got captured! They tried to pull the armies from Hammerfell too, which only had moderate success.

That's not been the case during any of the games. The provinces have always had their own local forces as well as the Legion, and even wars between them (eg. the war over Betony between Daggerfall and Wayrest). When the Legion gave up in Hammerfell the fight was continued by exactly those forces.3

Or, they'd achieved what they wanted in Hammerfell and had no reason to keep fighting there.

I don't personally believe it - I think they were whupped fair and square, having already lost too much of their strength in the war in Cyrodiil - but for completeness' sake it should be considered as a possibility.

Given that what they wanted in Hammerfell was to own bits of it and they ended up owning none of it, it's very unlikely they got what they wanted.