While the literal translation of Yakuza is "8-9-3," this is a generally accepted term given to such groups during the Edo period, when they were referred to in this manner because of an incident on August 26, 1756. Two people with the surnames Ito and Inoue were stabbed to death in Edo (now Tokyo). This incident was especially shocking because of a belief that swords were not supposed to be used against other Japanese people.  The government then investigated who these men were and any organized crime they might belong to.