Board Thread:Lore Discussion/@comment-2165692-20140531154239/@comment-27783182-20140531155555

Atmorans come from... well, Atmora, and descendants of the Nords. And Nedes are natives to Tamriel, and descendants from... Imperials, maybe?That's all I know...

The Redguards come from Yokuda, a continent east of Tamriel.

About interbreeding, probably. I'm not a lorewalker or loremaster, but these are my opinions.