Something called the Incarnation War... Demons rose up to wage war against all living beings, and were just barely stopped with the combined forces of dragons, elves, humans, and the gods...

The world was saved, but the losses were immense. The god who protected our lands was slain. The dragons were almost wiped out, and the elves went into seclusion...

What remained were the surviving demons... and humans, believed to be powerless against them.