However, as it has been found that standardized keyhole-shaped mounds first appeared during the Kofun period in the Nara basin and then spread to Kyushu and Tohoku, it is thought that the political power that had influence over those of other areas was established in the Nara basin.
対して、古墳時代に入ると規格化された前方後円墳が奈良盆地に発生し、急速に九州から東北まで普及していることから各地の政治勢力に一定の支配力を及ぼしうる政治権力が奈良盆地に成立したと考えられている。