There is a theory that suggests that although the sacred sword enshrined in Atsuta-jingu Shrine and the Imperial Household (the Yamato Dynasty) were originally unrelated, a mythical description was created in order to tie them together.
また、熱田神宮に祀られている神剣と皇室（大和王権）とは元々関係ないが、これを皇室を結びつけるために神話の記述が作られたという説がある。