Coming from the point of a UFO researcher and achiever of CHIM , this is a synopsis of what I speculate the races could be metaphoric of. The provinces could be a metaphor for star systems within the milky way. Another possibility could be all these alien races have come together onto this planet or whatever, called Tamriel or Terra/Earth.
Argonians - The similarities of a reptile alien theory and the argonians is the most obvious to a typical new-age hippy metaphysics buff. The theory suggests that dragon looking humanoid ET's from the star system Draco have been on Terra(Earth) since times of atlantis inhabiting a continent in the pacific (Lemuria/Mu)
Redguard - The theory here is that humans of the darker pigmentation came from Sirius star system(a&b c?) An african tribe in Mali called the Dogon tribe claim to have contact with amphibious beings from Sirius(Dog star)
Dwemer - This one was confusing but I have multiple theories including a technological/spiritual resemblance to the Atlanteans(i believe to be 1000x more spiritually/technologically advanced). Another is a resemblance to the disapearance of the Mayans. Or equally they could be metaphors for Aliens coming, inspiring change creating monuments of their technological prowess(like pyramids across the earth)and leaving.
Dark Elves - They could stand for many things including early civilizations like Mesoptamia/Sumer/Babylon, Or even the early U.S. with its slavery. I also thought they could be potheads with those red eyes/pale faces and Hack lo leaf
Akavir - Could be the astral realm with its demonic beast folk/lower vibrations
(Cont.'d)