User blog comment:Thedoucheinthenorth/The Civil War - Why it is great/@comment-2041603-20121103194321/@comment-5135631-20121104154944

No, they brainwashed him into thinking the infprmation he gave led the AD to take the Imperial City. Ulfric's rebellion was his own idea.

As long as the war finishes quickly, then the Thalmor are at a loss, as a quick victory for either side will either strengthen the AD's enemy or create a new one they have no influence over. The Thalmor want the war to continue for as long as possible.