It had been 5000 years since the Reincarnation Inheritance opened. Much had changed in that time but the greatest change was the Silver Dream Pavilion.
Thanks to the actions of Lind Frey to get the most in and the clear sacrifice he made to get as many as he could to survive, the powers cooled off on their machinations.
If only peace had been able to last during that time.
The Fiends had been unusually quiet so many had assumed they had been building up their forces once more. The Sovereign Tiers were suppressing things on their layer but resources had limits to extend such suppression to the other 3.
Further, the Heaven Realm Lands still had massive numbers of Fiends always rising up or being found to have enclaves of power still heavily entrenched but it was not them that started the first major war.
It was humans.