Shukun oshikome (detention of a lord by retainers) (主君押込)
Shukun oshikome (or simply called 'oshikome') is a practice seen in the samurai society beginning in the Kamakura period, and it especially refers to the forcible confinement of the allegedly misbehaving lord based on the decision made by Karo (chief retainers) and others after consultation. This is a type of coup d'etat in Japan. A historian, Kazuhiko KASAYA revealed the establishment and system of it.
Prehistory
In the samurai society of the medieval period, Confucianism was not so influential that vassals did not necessarily see their lord as all-important. A lord and his vassals were mutually dependant and cooperated with each other to form a community, and they often changed their partners and those relations were not fixed. Therefore, some lords who ignored their vassals' intention were dethroned through discussions by the vassals, and at times, a powerful vassal became the lord based on the consultation.
This trend became eminent in the Muromachi period, and the murder of Shogun Yoshinori ASHIKAGA by Akamatsu clan (Kakitsu War), dethronement of Shogun Yoshiki ASHIKAGA by Masamoto HOSOKAWA (Meio Coup) and the murder of Shogun Yoshiteru ASHIKAGA by Hisahide MATSUNAGA (Eiroku War) can all be understood as shukun oshikome of the shogun families. At that time, shugodai (deputy military governor) sometimes dethroned their lord, shugo daimyo (provincial military governor turned daimyo). These phenomena tended to be simply seen as gekokujo (an inverted social order when the lowly reigned over the elite) in the past, but as the study progresses on the form of territory ruling by daimyo in the Warring States period, more people think that the ruling system was never be autocratic and took into consultations and intentions of the vassalage. Based on this point of view, gekokujo is now generally understood as the phenomenon caused by this practice of shukun oshikome.
Edo period
In the Edo period when samurai ethics of seeing loyalty to lord as all-important were gradually established, the phenomenon was not seen with Tokugawa Shogunate Family at least, but the practice remained to be seen as an extraordinary step to forcibly confine lords who misconducted themselves. These actions were made because continuation of the family was valued. If the tyranny-caused damage become serious, or misconducts by a lord are discovered by the shogunate government, the family is seen as incompetent to rule the territory and is likely to receive a punishment such as transference from one fief to another, curtailment of its fief, and in the worst case, removal of samurai status and expropriation of territories.
The procedure was roughly established. If the lord misconducts himself, chief retainers admonish him to mend his ways. Such an admonition was a risky action that sometimes makes the lord angry and that the retainers who admonished might be slain by the lord himself, but to admonish was a duty for vassals to observe. If the lord does not mend his ways after admonitions are made several times, senior vassals including karo (chief retainers) gather and discuss the issue. If the discussion concludes that oshikome is unavoidable, it will be carried out.
With those who skilled in the martial arts or are strong-muscled in the position of Metsuke (inspector of foot soldiers) or higher in waiting in the side, chief retainers say to their lord, 'You behaved very badly, so you should be confined' and vassals take swords away from the lord and imprison him to a place such as a confinement room. The lord is confined for several months, during which he repeatedly holds talks with senior vassals including karo. If senior vassals including karo conclude that the lord fully reformed himself and will mend his ways, the lord is allowed to get back to the original position after making a written promise. The written promise says mending his ways, governing well and not retaliating upon vassals who confined him.
If the lord shows no sign of remorse or the remorse is seen as a pretense or the vassals think that the lord is highly like to sink into corruption and tyrannize again, the lord will be forced to retire, and the retirement is reported to the shogunate government and an appropriate person is chosen among legitimate children and brothers.
The confinement of Tsunamune DATE in 1660 was carried out under the approval and supervision of the shogunate government. This is the first case of government-approved kunshu oshikome. But on the other hand, if oshikome without governmental permission is discovered, punishment may be given.
These confinements were not always justifiable.
Some were just struggles for power, and in some cases, reform-minded lords were confined by their vassals who blamed the lord for his misgovernment to protect their vested interests
Yozan UESUGI, who is generally seen as a wise ruler, was once being driven to the brink of oshikome by his vassals who opposed to his reform (Shichike Disturbance).