In the Kanto region, including the Tama area, the period from the mid-sixth century to the mid-seventh century (until the Taika Reform) was a time when, in order to expand the sphere of influence in the mainland of Japan, the Yamato Regime fought battles with Mojin ("hairy people" which refers to natives of Ezo), who had influence in the Kanto region and northward, to conquer them or to prevent their strong resistance and attempted to mediate the power struggles among the regional clans.
6世紀中頃から7世紀中頃（大化の改新）までの多摩を含む関東では大和政権が本州での勢力拡大を行うため、関東以北に勢力のあった毛人（蝦夷）の同化や毛人の強い抵抗による攻防戦、地方豪族による権力争いの調停などを行っていた時代である。