The early periods of the era known as Advent are also known by another name: The Upheaval. Even after Anasatar was revived from its withered state, there was much to be done to bring it back to its former glory.
Where once a multitude of races had lived in harmony, there was now segregation. The new deities brought in by Lord Ao also brought with them their followers, followers who tended to be of a certain race. For a time there was little interaction between the races as they attempted to rebuild and make a home for themselves on the surface of a recovering world. However, as years passed and populations grew, conflict would inevitably occur.
These conflicts would evolve into bloody war during the first 1000 years of Advent, until an equilibrium would be found. An uneasy truce, marked by the occasional border skirmish would last until the next age during World Break