Kira Yoshinaka, better known as Kōzuke-no-suke, was a high ranking samurai who has been immortalized in Japanese culture as the notorious villain in Chūshingura, the story of the 47 ronin.

In 1701, Asano Naganori, the daimyō (feudal lord) of the Akō Domain, assaulted Lord Kira with his sword for unknown reasons. He was forced to commit seppuku (ritual suicide) following a brief tribunal. Enraged, 47 samurai who had sworn fealty to Lord Asano attacked Kira’s home at night. The ronin killed the lord along with several members of his clan. The 47 men were arrested not long after and were ordered to commit seppuku.

The story of their samurai loyalty has been adapted into countless bunraku and kabuki plays, novels, films, and TV series over the years. Many have taken artistic license to explain the motive behind Asano’s assault, which usually boils down to Kira insulting him or Asano refusing to bribe the lord.

However, many historians today propose that Kira may not have been the villain the story depicts, and his character deserves re-evaluation. Kira was greatly admired by his vassals as a fair and good lord. He created a salt industry in the region and expanded rice paddies for cultivating. Evidence suggests that the reason why the 47 ronin attacked Kira was not revenge, but perhaps something more selfish as they waited almost a year to attack.

Either way, after the incident Lord Kira’s vast mansion in Edo, which was reportedly over 2 acres (8,400 square meters) at that time, was confiscated by the Edo bakufu (government). It was then turned into a residential section. 

In 1934, locals bought 98 square meters of land surrounding the Mishirushi-arai-no-ido, the well in which Kira's decapitated head was reportedly washed, and donated the space to Tokyo City. Their goal was to get the section preserved and opened as a public park.

The park, now named Honjo Matsusaka-chō Park, consists of several exhibits including an Inari shrine, a seated statue of Lord Kira, and stone memorials for the victims of the Akō incident.

Every year on December 14 (the day the incident took place), the town council holds the Gishi Festival where the raid on Lord Kira's mansion is remembered.