According to the Japanese historical legends, the office of Kubō-Sama, originally limited to the infliction of punishments and the suppression of crimes, was shared, for many ages, between the two families of Genji and Heiji, till about 1180, when a civil war broke out between these families, and the latter, having triumphed, assumed such power that the Dairi commissioned Yoritomo, a member of the defeated family of Genji, to inflict punishment upon him. Yoritomo renewed the war, killed Heiji, and was himself appointed Kubō-Sama, but ended with usurping a greater power than any of his predecessors