Akamatsu Mitsusuke

Akamatsu Mitsusuke (1381–1441) was a samurai who served as Guardian (shugo) of the three provinces of Harima, Bizen, and Mimasaka under the Muromachi Shogunate. He earned a place in history through his assassination of the sixth shogun, Ashikaga Yoshinori, during the Kakitsu Rebellion in 1441. Mitsusuke's unprecedented act of killing a shogun greatly damaged the authority of the Muromachi Shogunate and became one of the distant causes leading to the Ōnin War.

The Akamatsu clan, Mitsusuke's house, was a distinguished family that had obtained the position of guardian over Harima and other provinces through its service to Ashikaga Takauji during the upheavals of the Nanbokuchō period. However, under the autocratic rule of Ashikaga Yoshinori (a shogun called "Terror of All Men"), many guardian daimyo experienced purges and persecution, and Mitsusuke himself became a target. Fearing the reduction of his territories and persecution of his clan, Mitsusuke is said to have resolved to assassinate Yoshinori in a preemptive strike.

On June 24, 1441, Mitsusuke invited Yoshinori to his residence under the pretext of celebrating a victory in the Yuki Battle and assassinated him by dispatching assassins during a Sarugaku performance—the Kakitsu Rebellion. However, this uprising did not succeed. The Shogunate's great forces invaded Harima, and after Mitsusuke withdrew to Shiroyama Castle (in Tatsuno, Hyogo Prefecture), he died by his own hand in September of the same year.

Regarding his connection to swords, the Akamatsu clan controlled famous sword-smithing centers in Harima and Bizen and maintained close relations with the sword smiths of Bizen Osafune. The blade Mitsusuke used to assassinate Yoshinori has been transmitted as the "Kakitsu Tanto" and is recorded in the history of swords as a witness to one of the most dramatic assassinations in Japanese history.