Board Thread:Lore Discussion/@comment-13417807-20130726023954/@comment-15145664-20130811210834

I never said that they did. But Tiber Septim set out to conquer Tamriel because he had a dream or something. Maybe the Greybeards told him to do it... I need to check his wiki page again.

Regardless, nearly every race on Tamriel has fantasized about conquest at one time or another and several have tried. The Aldmeri Dominion is only different because it seems to care about religious preferences while the Empire did not. (i.e. Tiber Septim allowed the Tribunal to remain in power in Morrowind)