First 30 mins of Skyrim

Interesting that you can start the tutorial by entering the Keep with either Hadvar (Stormcloak) or Rolof (perhaps a guard?), so it appears you have some branching paths even from the very start of the tutorial quest.

I would imagine you can probably take a very different approach and attempt to speak with the guards with sword sheathed, (they only start attacking the PC after he draws his sword the first time in the Keep) sneak past them, side with neither group or simply attempt to kill every Stormcloak and Legion guard you encounter.