These five kings, in return of the tribute, were taken into Sakuho system as 'Wakoku-o' by Chinese Dynasty, and it is estimated that this title was used diplomatically.
これら五王は、朝貢の見返りに、中国王朝から「倭国王」に封じられており、対外的にはこの称号を名乗っていたと推定される。