As part of the Taika Reform (645), which aimed at a centralization of the administration following the Chinese model (ritsuryō), the kokufu and with it the office of the kokushi, replacing the older Kuni no miyatsuko, developed in the 660s.
[1] The Wamyō Ruijushō (Collection of Japanese Names) from 935 contains the earliest listing of the capitals of the provinces and their location.
[2] When during the Muromachi Period, starting in the 14th century, the functions of the kokushi were increasingly transferred to military governors or constables (shugo), the provincial governments (kokuga) lost their importance.
In the center of the kokufu lay the provincial government (kokuga) with its offices (administration, farming, finance, police and military, adjudication) and the official building complex of the kokushi, known as kokuchō (国庁).
[3] When the shugo replaced the kokushi, their administration, the shugosho (守護所) was occasionally found in or near the buildings of the kokuga.