User blog comment:Zippertrain85/"Why the Empire Should Prevail Over the Stormcloaks" refuted (part 1)/@comment-4225295-20131206210942/@comment-12599067-20131207210511

1) Half of Elsewyr supports the Dominion, and I'm pretty sure at least part of Valenwood supports the Dominion. That said, it would basically be Skyrim vs. Cyrodiil and Alinor. The rest of the Legion would swoop in and kick Ulfric's shit in, and even if he defeated them, he'd have to deal with the rest of the Dominion.

2) Half of Elsewyr for starters, and they probably have a significant presence in Valenwood.

3) You forgot Northwatch Keep. If there are about 100 people at the Embassies, there would surely be quite a few maintaining the keep. And the Justiciars are probably not from the Embassies alone, there is Thalmor presence in quite a few Holds of Skyrim, such as Markarth and even Stormcloak-controlled Winterhold.