The Kanpyo-Engi Togoku War (寛平・延喜東国の乱)
The Kanpyo-Engi Togoku War was a war raised by bandits in the Kanto region in the middle era of the Heian period. In 889, MONONOBE no Nagauji, the head of a group of bandits, and others started the war.
In the era from the eighth century to the ninth century, the troop system (in ancient Japan) was abolished. Because nationally legitimate permanent troops became extinct, the security of local areas deteriorated, and it became an ordinary state throughout the nation that bandits were rampant against stringent collections of taxes by kokuga (provincial government offices). In particular, in Togoku throughout the era from the middle of the ninth century to the end of the century, barbarians raised rebellions one after another in addition to bandits whose activities had become more active, deteriorating security markedly. The Imperial Court sent nobles concerned with military affairs to suppress these activities as kokushi (provincial governors), and in addition, took the measure of placing kebiishi (a police and judicial chief) at kokuga as well. However, the activities of bandits could not be suppressed, with the war being raised.
Although its details are not known, it is described in "Fuso Ryakki" (A brief history of Japan) and "Nihongi Ryaku" (Summary of Japanese chronologies) that it took around ten years to suppress the war. However, even after the war was suppressed, the activities of Shubano-to groups (that were entrusted to the work to convey goods, but sometimes behaved like bandits as well) became rampant conspicuously, making the state remain unstable.
In this process of suppressing the war, the military system was reformed in the Engi (901 - 923) era, making less restrictive the regulation of kokuga mobilizing people for military purposes. Formerly, the central government possessed the right of mobilizing military personnel, but according to a theory, the system concerned was changed to the following one: An Oryoshi, a police and military command, was appointed to each province, and when instructed by Zuryo (the head of the provincial governors) who received an official document instructing the suppression of a rebellion, the Oryoshi mobilized samurai in the province to suppress the rebellion.