From the end of the ninth to the beginning of the tenth century, it was no longer possible to keep the Ritsuryo system (a system of centralized government based on the Ritsuryo code), based on the huge bureaucratic organization and the sophisticated statutory system, and a dynastic nation-state was newly established, in which certain administrative and legislative authorities were undertaken by the local officials and central bureaucrats.
9世紀末から10世紀初頭にかけて、巨大な官僚組織と精緻な法令システムを前提とする律令制の維持がもはや不可能となり、一定の行政司法権を地方官や中央官庁へ請け負わせる王朝国家が新たに成立した。