Through the empowerment of zuryos, they incorporated the local ruling families leading the people into a kokuga government system, instead of the jo (the third-ranking local administrator) and sakan (the fourth-ranking local administrator) who were reluctant to accept the one-sided orders they issued because jo and sakan were also old administrative aides from the same class, in order to strengthen the governance of both tax collection and military affairs.
この権限拡大を背景として、受領たちは租税収取・軍事両面において統治を強化するため、旧来の補佐官で同一階層出自ゆえに一方的に使役しがたい掾（じょう）、目（さかん）に替えて、国内の豪族・有力者らを国衙の体制に組み入れた。