Dawn Era

The Beginning of Time
The Dawn Era is the Era in which the Cosmos was formed out of The Void (Sithis), and with it the world of Mundus, though they are both more commonly referred by their Elvish variants, Nir and Nirn, respectively. It was during this time that Akatosh (Aldmeri: Auriel) forms and with him the concept of time begins to take hold. Other gods (Aldmeri: et'Ada) follow the example set by Akatosh and begin to create other aspects of the Cosmos.

Lorkhan and the Mortal Plane
Lorkhan, the "Missing God", the "Creator", the "Trickster", whatever he is called he is the et'Ada credited with the creation of the mortal plane Nirn and has a place in every Tamrielic religion. Best known in his Aldmeri name Lorkhan (meaning "Doom Drum") convinced (or tricked, depending who you ask) some of the other original et'Ada to create the mortal plane.