- « "Some of us want to rule the world, Jack, others like you wish to save it, others still, like our honour-obsessed Japanese friends, wish to end it." »
- — Wolf on the Brotherhood
Before The Six Sacred StonesEdit
In the fallout of the Hiroshima bomb and World War II, several people throughout Japan gathered together and formed a group that would attempt to restore Japan's honour, even if it took forever to accomplish.
After Akira Isaki's parents died in a car crash, he was taken in by his grandparents, who were members of the Japanese Blood Brotherhood, and indoctrinated with their ideals.
At some point, one of their members, anthropologist Yobu "Tank" Tanaka, met Max Epper, and during their occasional collaborations Tank learned of Epper's discovery of the existence of the Dark Sun, which would destroy the world if they did not restore the ancient Machine. Tank saw this as the Brotherhood's chance to destroy the world and redeem Japan's dishonour, and so with their approval, as well as the support of Japan's government, Tank began researching the Machine with Wizard to seek opportunities to sabotage it.
When the Brotherhood discovered that the rogue American Commander-in-Chief's In Extremis Force was preparing to restore the Machine, they had Isaki, currently operating as a United States Marine, request a transfer to the CIEF so that he could find an opportunity to derail the mission.
The Brotherhood has only one desire; to restore their honour for the disgraceful treatment they received from the rest of the world following World War II. They do not care if it costs them their lives, as a self-sacrificing death is the greatest honour. This also allows them to follow the belief that by preventing the restoration of the Machine, their honour will be restored for the entire world's destruction. The Brotherhood does not believe that Japan's current placing as a strong country in the modern world is enough, and even the Japanese government supports them.
- After the events of The Five Greatest Warriors, it can be presumed that a few members of the Brotherhood remain.