Board Thread:Lore Discussion/@comment-76.97.80.106-20130811163656/@comment-75.75.80.173-20140424173959

There could be some future alliance if the Empire splits, which could act similarly to the Empire, but keep the traditions & independence of the nations  ( provinces ). The Thalmor threat would certainly be a good reason to form some sort of Confederation or Alliance[s].

Argonia, Skyrim, Hammerfell, & Cyrodiil all likely have bones to pick with the Dominion.

Morrowind is least likely, but still has some potential to join, but they'll be most nuetral if the situation arises. Dunmer hold many grudges to the rest of Tamriel for varying reasons, & are literally cleaning up the ashes of their homeland  ( those still there ).