Kokuga (provincial government office compounds) (国衙)
Kokuga is a term for describing the section in which a government office, a Kokushi (provincial governor) executed the local government functions of the ritsuryo system (a system of centralized government based on the ritsuryo code) in Japan, used to be located. Leading up to the Heian period, it was generalized that a government office of the Kokushi (called Kokucho [local government]) itself was called Kokuga and the Administration and Judiciary structures of the Kokushi were called Kokuga.
In some cases, a ranking government official (lower or middle ranked) and other government officials, those who served the Kokuga, were called 'Kokuga.'
The city area where developed around Kokuga was called kokufu (provincial capital).
Ruins and land-use plans (or zoning plans)
The main ruins of Kokuga include Suo Kokuga (Hofu City), Hitachi Kokuga (Ishioka City), Omi Kokuga (Otsu City), and Tosa Kokuga (Kami City). These ruins of Kokuga showed that each land-use plan for the Kokuga shared several common points.
As a central facility of the Kokuga, Kokucho Seiden (main palace for the local government) was established. In some of the Kokuga locations there were a mae dono (front palace) and a ushiro dono (rear palace) situated at the front and the back of a seiden (main palace). Seiden was often built at the front to the north side, facing south of the premises. Then, wakiden (hall standing nearby main hall) were situated on the east and the west side of the seiden and each of the wakiden were called the higashiwakiden (palace located on the east side) and the nishiwakiden (palace located on the west side). The center of the Kokuga was maintained as open space. All of the buildings on the premise of the Kokuga were situated in a symmetrical manner.
These kanga (government office) buildings were neatly situated within the area surrounded by tsuijibei (a mud wall with a roof) and hottate bashira bei (a wall with pillars embedded directly in the ground). This Kokuga area was often divided into sections in multiple meters of ten to a hundred square.
A building site of Kokuga was surrounded by a wooden fence and tsuijibei (a mud wall with a roof) made of hottate bashira (pillars embedded directly into the ground) and a ditch. The gate was built on the south side. Building structures of the Kokuga were restricted to two types of architectural methods: Hottate bashira and soseki dachi (a structure built with a stone foundation).
However, the scale of a Kokucho Seiden and a Kokuga area varied with province and time period. Thus, there were more different points than common points when comparing each of the land-use plans of the Kokuga. Around the Kokucho, there were workshops for making office stationery and expendable supplies, equipment and weapons and Kuriya (kitchen) for dining and other functional places (this place was called a zoshi [a room in the Imperial court especially made for ladies of the court]). In addition, there were other buildings called kokushi -kan where was a house of a provincial governor and a shoso (public repository) which was for keeping collected land taxes. The layout of these architectural buildings completely differed from each province.
It is believed that the earliest type of Kokuga appeared during the development stage of the Ritsuryo system which established in the late seventh century. However, in those days, the local political systems were not fully developed. Therefore, Kokuga had not been established firmly as it can be seen later. From early to middle eighth century, Kokuga was conducted in a stable manner. Therefore, it is believed that Kokuga was formed during this period.
Under regulations of the Ritsuryo codes, the Kokuga employed the kokushi shitokan (four officials of the provincial governor) as follows: Kami (director of the provincial governors): Suke (vice governor of provincial offices, the second ranking government official): Jo (facilities manager, secretary of provincial offices, the third ranking government official): Sakan (clerk of provincial offices, the fourth ranking government official) and a secretary called Shisho (a clerk, a person doing miscellaneous duties on documents). As for the other employees, Kokuga employed specialists such as Kunihakase (teacher of Japanese classical literature), Kuniishi (local governmental doctor) and Kokushi (the most reverend priest) and a Yotei (a mandatory laborer) who was requisitioned by the zoyo (irregular corvee). The total number of workers in small provinces came to dozens of people and in major provinces came to a considerable workers such as several hundred people. And the city-like territory was formed around Kokuga.
In ninth century, the Ritsuryo system gradually detached itself from the actual social situation and governmental administrations reign over the locals became more difficult. Then, in the early part of tenth century, the Imperial Court executed a national governmental systems reform that transferred the greatest authority over administration to Kokushi (This system established by this reform was called the system of the dynasty state). In order to cope with the massively increased power, the Kokushi attempted to strengthen the structure of Kokuga. So, the Kokushi modified the Kokuga, establishing several departments such as a department to control the collection of taxes (zeisho [tax office], tadokoro, daichosho [the major accounting and reporting office], suitodokoro [teller's office], and others), a department in control of military affairs (kondeidokoro [military office], kebiishi dokoro [police and judicial office], umayadokoro [stable office], and others), a department in control of the shomu (land management) and routine tasks (mandokoro, choso [checking office], saikudokoro [tooling office], zendokoro [food office], and others). In those days, a Kokushi did not leave for the assigned province (called yonin [remote appointments]) and sent out a mokudai (deputy kokushi, or a deputy provincial governor) instead, who was a deputy and also director to the assigned province. Then, the cases that Kokushi put a local influential person and government official in charge of Kokuga (Zaichokanjin [the local officials in Heian and Kamakura periods]) had been steadily increased. In reality, during the eleventh and twelfth centurys, the Zaichokanjin controlled Kokuga politics and Zuryo (the head of the provincial governors) Kokushi could not execute governing duty of the province without Zaichokanjin's political power.
From the middle of eleventh century, a number of Shoen (manor in medieval Japan) increased remarkably, and subsequently Koden (territories administered directly by a ruler) which was originally controlled by Kokuga decreased gradually. In order to confront to this problem, Kokuga arranged and united all of the controlled territory of a koden domain into one unit. Then, Kokuga reorganized the rules of the koden implementing the following system: Kori (district, a unit of 2-20, 50-home neighborhoods or townships, in the Ritsuryo period), Ho (district, a unit of 5-home neighborhoods or townships, in the Ritsuryo period), Go (district, a unit of 50-home townships [comprised of 2-3 neighborhoods], in the Ritsuryo period), and Jo (a unit or a system to divide lands in the Ritsuryo period). Then, Kokuga succeeded to territorialized their own controlled territory. These newly established controlled areas of the Kokuga were called Kokugaryo (territories governed by provincial government office).
In the Kamakura period, bakufu (Japanese feudal government headed by a shogun) established Shugo (provincial constable) in each province. Shugo had an approved power only applicable in the right to judge criminal cases and did not disturb the sovereignty of the Kokuga. However, the shugosho (provincial administration) where Shugo resided was often built near-by the Kokuga property; so, the Kokuga and Shugo began to develop a tendency in the gradual integration of their functions.
In the Muromachi Period, Shugo was given not only the right to judge criminal cases but also more powerful authority of administration. Thus, Shugo had aggressively encroached on the authority in the administration of the Kokuga. As a result, during the early Muromachi Period, the political structure of the Kokuga was absorbed by Shugosho and practically most of Kokuga disappered.
The name of Kokuga Ruins
Although there are few cases remaining Kokuga as the place name, Hofu City Kokuga (Suo Kokuga ruin) is relatively famous.
There are other places named Kokuga, for example:
Misakacho Kokuga, Fuefuki City, Yamanashi Prefecture (Kai Kokuga ruin)
Matsuidamachi Kokuga, Annaka City, Gunma Prefecture (Kozuke Kokuga ruin)
Zindaikokuga Minamiawaji City, Hyogo Prefecture (Awaji Kokuga ruin)