Imperial's or Stormcloaks?

[Elizabeth]

Which is Canon, Dragonborn joining Imperials or Stormcloaks? I read another article and I do remmeber the old Imperial Legion man at Ghostgate named Wulf (who later turns out to be Tiber Septim) saying this.


Quote from Wulf:
Poor Old Emperor: "The Emperor is getting old. Don't know how much longer he'll hang on. So is the whole Empire, for that matter. Getting old, that is. The Emperor and the legions have held the Empire together for hundreds of years. It's been a good thing, by and large. But maybe it's time for a change. Time for something young and new. What? No idea. Because I'm old. Old dog doesn't get new ideas. But maybe young folks like you should try some new ideas. I don't know. Could be messy. But change is never pretty."

[Raymond from Animal Crossing]

The likelihood of the Empire winning is pretty much canon: If The stormcloaks win, Skyrim will just be taken back by a proper legion stuck behind pale pass, As the Legion present in Skyrim are "Farmer bois" according to Tullius.
Likewise, The Stormcloaks, if faced with another Great war, would probably side with the Empire to defeat their common enemy: Aldmeri Dominion. (Simillarly to Hammerfell). If They got the victory they wanted, they may join with the Empire again as Talos worship would be fully-legalised again.