Eight hundred years ago, the world was protected by Eight Shinigami Legions, a group of dedicated to to preserving the world order. Led by the Grim Reaper himself, the group faced a betrayal by Death's own apprentice, who became a kishin and wrecked havoc on the world with his powers of insanity.

Forced to be sealed away by his own master, the group disbanded. The Grim Reaper then founded Death Weapon Meister Academy (also by the acronym "DWMA") to act in it's place. Students within the school,