" Eons ago, there were a group of Elven Magi/Order (Ayleid) that controlled everything and used perverted magic and made slaves of men. They used these slaves for entrainment/ perverse things. Until a slave woman named Andraste (Alessia) led a slave revolt with the aid of the Maker (Akatosh) and became divine/ one with the Maker in her death. She basically sets up the first human empire and religion and starts the worship of the Maker (Aedra/Akatosh).
The only divergence seems to be that she was killed in the process of bringing down the Magi Order, and did not survive to live as Empress.