If you look at the wall in the new trailer when the narrator says "When the sons of Skyrim will spill their own blood...", you can see the two factions on either side of the mural where on the left they seem to be dressed in more traditional Nordic attire while the opposing side is dressed in an imperial-roman or anglo saxon attire. Then also look at the guards/soldiers that are walking around the village in the trailer wearing the romanesque/centurion armor. Was there an occupying imperial force in Skyrim with perhaps an undercurrent of independence-minded traditional "Skyrimians" fighting for an ancient nordic culture?
Does anyone know any canon on the setting here? I would really be interested to know more about the setting.
*Edit for punctuation