The Buei Disturbance (Buei sōdō) occurred in Kanshō 6 (1465) as an internal conflict within the Muromachi bakufu.
Ise Sadachika, the secretary of the mandokoro, a political organ of the shōgun family for nobles of the third rank or above, intervened with the consent of Ashikaga Yoshimasa, the eighth shōgun, in a disturbance within the Shiba clan who were one of the deputy families of the bakufu. Sadachika mediated between Shiba Yoshitoshi and Shiba Yoshikado in pursuit of his own interests, causing confusion in the bakufu administration. Influential figures including Hosokawa Katsumoto and Yamana Sōzen shared a sense of dismay at Sadachika’s intervention in the succession affairs of the deputy family notwithstanding his role as secretary of the mandokoro. In 1466, they collaborated to expel Sadachika from the bakufu administration in an event known as the Bunshō Political Incident (Bunshō no seihen). In the background, the expulsion of Ashikaga Yoshimi who was slated to become the next shōgun further complicated the situation.
Meanwhile, the formation of an army in Kantō to conquer Ashikaga Shigeuji, the Koga kubō who opposed the bakufu, caused a series of changes in family leadership. Ashikaga Masatomo, the Horigoe kubō, the branch organ of the bakufu in Kantō, did not have an army under his direct control so efforts were made to dispatch the Shiba army under the bakufu to Kantō; however, Shiba Yoshitoshi disobeyed these orders. This escalated into a battle against Kai Yukihisa, the secretary to the Court for the Shiba family, in an event known as the Battle of Chōroku. This resulted in Yoshitoshi being removed from the line of succession and his son, Shiba Matsuōmaru (later known as Shiba Yoshihiro), became the twelfth head of the clan. Thereafter, the secretary for Masatomo named Shibukawa Yoshikado (the son of Shibukawa Yoshikane) then became the successor to the clan with the aim of enabling Yoshikane to manipulate the Shiba army.
However, a conflict with the Ōgigayatsu-Uesugi family caused Yoshikane to lose his standing, after which Yoshikado’s role as head of the clan lost its purpose. Once again, Ise Sadachika pulled together an expeditionary forces led by Shiba Yoshitoshi in a bid to restore his power. After being unilaterally removed from the line of succession, Yoshikado joined with a faction under Yamana Sōzen to counterattack, ousting Sadachika, Kikei Shinzui, Yoshitoshi and Akamatsu Masanori, thereby causing Sadachika’s plan to fail.
Later, a confrontation between Katsumoto and Sōzen triggered the Ōnin-Bunmei War, whereby Yoshitoshi, Yoshikado, and Masanori joined the Eastern Army affiliated with Ashikaga Yoshimasa (the shōgun). As an outcome of victory by the Eastern Army, Yoshitoshi and Yoshikado recovered the inheritance of their military family, while Masanori recovered the inheritance of the Akamatsu clan as well as the role of military governor of Harima Province. Ise Sadachika and Kikei Shinzui received pardons and were allowed to return to the capital of Kyōto, after which each of them regained their positions. Nevertheless, Sadachika and Shinzui were not given allowance to operate, whereupon Shinzui died in 1469 and Sadachika died in 1473.