Can anyone fill me in on what went on on a national level between the Great War and Ulfric's rebellion? Were there any major events between 176 and 201? I've looked and it seems to be a bit of a blank period in Tamriel.

"There is peace now, and that peace will continue for as long as it suits our needs. But make no mistake, this is not a peace forged out of necessity between rival nations of equal strength. It is more like the calm between storms. And the next storm, I think, will be far deadlier than the last."

-Ondolemar [Best damn character in Skyrim because of these lines, and the voice actor]

There's small bits of info on hammerfell, cyrodiil, high rock, and skyrim. But that's about it. Dominion territory is understandably in an intel blackout, and Black Marsh doesn't really care to communicate with the empire either.

You can assume that there's a general sense of lawlessness that's falling over Imperial territories as the bureaucracy's authority begins to fail. We know from the Dark Brotherhood quest that Cyrodiil is in dire straits, while Hammerfell has forced the Thalmor out of its territory but will likely find itself embroiled in a low-level civil war between its perennial factions (something that the Thalmor might exploit at a later date to actually create a hot civil war, rather than something along the lines of the House Wars in Third Era Morrowind). High Rock has probably been decentralized from the get-go, since it took Numidium to forge some small notion of central authority and Imperial loyalty in the Iliac Bay region in Daggerfall, and after the end of the Septim dynasty I can easily see that loyalty falling to the wayside; thus, the rumblings from that area of the map are likely to be more like background noise at this point, always there but minor. The state of Morrowind is constantly being brought into question on this forum, so there should be some good information about them from folks that actually know what they're talking about if you dig. Other than that, I think the rest has been said.

About Hammerfell, there's some info in one of the books (I think it's called The Great War) and in those ruins invaded by the Redguard necromancer.

Redguard nobility refused to accept the White-Gold Concordat because, apparently, it included a clause that gave to the Dominion the southern portion of Hammerfell. Titus II was forced to officially renounce Hammerfell while the Thalmors invaded it. The Redguards, understandably, felt betrayed; they sought the help of the Nords petitioning Ulfric but he, too, refused to join forces in order not to upset the empire (maybe he wasn't ready yet to start an uprising).

Despite the odds, the Redguards were able to fight the Thalmors to a standstill, although the war lasted for five more years. The second treaty of Stros M'kai in 4E180 signaled the end of hostilities and the complete withdrawal of Aldmeri forces from Hammerfell.

I don't think we can say that a good majority of redguards wanted help from Ulfric because of one necromancer, she never really stated that a lot of redguards wanted it so it could just be that the Necromancer wants vengeance because she went insane from the death of her husband. I really don't think people should use her as a source for the Redguard general opinion of the empire. Now I'm not saying the redguards don't feel betrayed but I'm saying is they didn't turn to Ulfric and they don't want to raise armies of dead soldiers to wipe out the stormcloaks for not helping them, the empire and the Dominion like the necromancer wanted.