The world of Agarest was brought forth by the twelve divine children of the ultimate god, Lenion.
Although it was meant to be a physical manifestation of the perfection of the god's ideals, relentless in-fighting eventual led to the division of light and darkness, corrupting their creation. It was out of this turmoil that the three great wars of the gods began.
The first war divided the world, and the gods themselves, between light and darkness.
The second war introduced chaos and strife into the world.
The third war saw the god of light defeat and imprison the gods of darkness.
While the gods of light were finally able to claim victory, it came at a terrible cost. The world they fought to protect was devastated by years of conflict and the races they had created were threatened with extinction. Overcome with grief and horror, they sacrificed their own bodies to not only replace the world they had destroyed and to seal the gods of darkness away, but to create a new species to replace the ones they had inadvertently slaughtered.
That new world is the Agarest of today.
Before they departed for their own realm, the gods of lights left groups known as "guardians" on each continent and entrusted them with the tasks of watching the "pillars" in which the dark gods were imprisoned. Since that time, they have continued to fulfill that duty. And although they were also given the responsibility of guiding and nurturing the new race, the guardian clans eventually grew estranged and isolated from the rest of the world's peoples.
Time continues to flow towards its incomprehensible end and several eons have passed since the rebirth of the world. The truth has been transformed into barely remembered legends teetering on the edge of irrelevancy, and the authority and influence of the guardian clans has all but faded away.
One day, the world was engulfed in a single flash of brilliant light. It was more destructive than sublime, and looked like the type of lightning that makes one think of the rage of the gods. With it came a scouring of the world not seen since the original war of the gods. In addition, the people who lived on the continent from which the light originated were never heard from again.
That fateful day became known as the "Day of Light" and it marked when the world began to change. It also signified the start of the demon plague that spread throughout all of Agarest.
At the center of all of these events is Weiss, a young man who was given the responsibility of being the Spirit Vessel after committing the sin of killing a god. His memory was all but destroyed, with only the knowledge of his name remaining. It was only when meeting the mysterious Eva does he learn of his crime of deicide and of the penance that had been given to him, which is to retrieve the fractured power of the god and store it within himself in order to resurrect the god he had slew.
Those who betray the trust of the gods will be condemned to pay for their sin forever in the void between where everlasting life and eternal damnation meet.