The human realm never had peace since Luca's reign was overturned. The people trained to protect were divided. Some chased after the power while others tried to save what was left of it.
It wasn't an easy feet for them to accept.Although life wasn't peaceful, people felt free. The huge taxes imposed on them were reduced to a manageable amount.
Even the most ignorant one knew that the realm couldn't run without its people's contributions. A lot of amends were made as the new people in leadership took the mantle of power.
Despite this changes, not everyone was happy. The wealthy scion in the society were especially displeased. The changes brought about didn't favour them. On the contrary, it was a disadvantage for them.
That was one of the contributing factor to the current state within the human realm. The realm wasn't spared from the inferno that destroyed things in the other two places.