The basic run-down on the situation at the start of the game. Here is a link to the entire Campaign Player’s Guide I whipped up.
Many groups have been hired in the last several months to go out into the south. Reclaim old Hammerfell roads, improve relations with the small surviving communities, and carve a path towards the old Empire. That’s what you thought you’d been gathered for.
But you’re a bigger group than the others, with more supplies.
This is because you are being sent to the end of the line.
Officially, your job is to create an anchor for the new trade route and perhaps assist in organizing the locals in preparation of the Empire’s expansion.
Unofficially, you have been picked for the purpose of carving out foothold in the Central Province. A stable steading, a healthy fief, even a brand new city state if you are particularly ambitious. Whatever the case it’s the hope of several powerful representatives in each of High Rock’s kingdoms that they have either an influential new ally in Cyrodiil or are in a position with strong leverage should being absorbed into the new Empire prove the smarter move.
A new Aldmeri Dominion (alliance between the Altmer and the Bosmer nations) arose, to protect the interests of and restore proper power to the Mer, led by the Thalmor (who wished to wipe all traces of man’s Empire from the world). The Dominion claimed responsibility for ending the Oblivion Crisis, for restoring three of the moons that appeared to be missing for two years, and many other things.
There was a big battle, which ended with the White-Gold Concordat. This was seen by leaders in Skyrim as an outrage against Talos, whose worship was forbidden under the treaty, and a betrayal by Hammerfell, which had some of its coastline ceded to the Aldmeri Dominion in the deal.
Hammerfell cut ties with the Empire and drove out the Aldmeri. Skyrim went into revolt. The war broke out again, in what would eventually be called The White-Gold Wars.
Ancient magics were unleashed on all sides. At one point there are rumors that a major battle with most of the forces on all sides was swallowed whole into a Daedric realm, and over a century later combatants may still stumble into the world in the midst of life-or-death struggle. At one point or another Cyrodiil was held by a Nord, a http://www.uesp.net/wiki/Lore:Redguard, and a creature which the Aldmeri Dominion claimed was an ancient Ayleid Prince. Humans were crushed and collected into camps by that last, with slavers making it almost as far as High Rock and terrible diseases sweeping into some of the cities.
But, eventually, all fell. Imperials, Redguards, Bosmer, Altmer, and even the Beastfolk were greatly weakened by the wars. There have been scuffles, but very little order in the south and with Hammerfell so terribly weakened there is a great lawless stretch between High Rock and Cyrodiil.
Now, though, someone has been sitting as self-proclaimed emperor for half a decade. Perhaps it’s time to reach out, and take a hand in what comes next.