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

[Keltest]

I don't know who would have risen to be the figurehead without Ulfric, only that someone would have. You're right that it probably wouldn't be a noble, and without a noble patron the secessionists likely develop very differently, but there would still be that anti-imperial sentiment and it probably still turns into a violent civil conflict.

But why? Without a powerful and influential figure to lead them, how does the grumbling turn into civil war?