Chūshingura (忠臣蔵; Japanese pronunciation: [tɕɯː.ɕiŋ.ɡɯ.ɾa, -ŋɯ.ɾa], lit. 'The Treasury of Loyal Retainers') is the title given to fictionalized accounts in Japanese literature, theater, and film that relate to the historical incident involving the forty-seven rōnin and their mission to avenge the death of their master, Asano Naganori. Including the early Kanadehon Chūshingura (仮名手本忠臣蔵), the story has been told in kabuki, bunraku, stage plays, films, novels, television shows and other media. With ten different television productions in the years 1997–2007 alone, Chūshingura ranks among the most familiar of all historical stories in Japan.

The historical basis for the narrative began in 1701. The ruling shōgun Tokugawa Tsunayoshi placed Asano Takumi-no-kami Naganori, the daimyō of Akō, in charge of a reception of envoys from the Imperial Court in Kyoto. He also appointed the protocol official (kōke) Kira Kōzuke-no-suke Yoshinaka to instruct Asano in the ceremonies. On the day of the reception, at Edo Castle, Asano drew his short sword and attempted to kill Kira. His reasons are not known, but many have suggested that an insult may have provoked him. For this act, he was sentenced to commit seppuku, but Kira did not receive any punishment. The shogunate confiscated Asano's lands (the Akō Domain) and dismissed the samurai who had served him, making them rōnin.

Nearly two years later, Ōishi Kuranosuke Yoshio, who had been a high-ranking samurai in the service of Asano, led a group of forty-six/forty-seven of the rōnin (some discount the membership of one for various reasons). They broke into Kira's mansion in Edo, captured and killed Kira, and laid his head at the grave of Asano at Sengaku-ji. They then turned themselves in to the authorities, and were sentenced to commit seppuku, which they all did on the same day that year. Ōishi is the protagonist in most retellings of the fictionalized form of what became known as the Akō incident, or, in its fictionalized form, the Treasury of Loyal Retainers (Chūshingura).

In 1822, the earliest known account of the Akō incident in the West was published in Isaac Titsingh's posthumous book Illustrations of Japan.

In the story of the 47 rōnin, the concept of chūshin gishi is another interpretation taken by some. Chūshin gishi is usually translated as "loyal and dutiful samurai". However, as John Allen Tucker points out that definition glosses over the religious meaning behind the term. Scholars during that time used that word to describe people who had given their lives for a greater cause in such a way that they deserved veneration after death. Such people were often entombed or memorialized at shrines.

However, there is a debate on whether they even should be worshiped and how controversial their tombs at Sengakuji are. Tucker raises a point in his article that the rōnin were condemned as rōnin, which was not an honorable state, but in the end their resting places are now honored. In other words, it is as if those that regarded the rōnin as chūshin gishi were questioning the decision of the Bakufu (the shogunate, the authorities who declared them rōnin), and perhaps even implying that the Bakufu had made a mistake. Those recognizing the rōnin as chūshin gishi were really focusing on the basics of samurai code where loyalty to your master is the ultimate and most sacred obligation.

In Chinese philosophy, Confucius used to say that the great ministers served their rulers the moral way. Early Confucianism emphasized loyalty, the moral way and objection and legitimate execution of wrongdoers. Chūshin gishi is interpreted as almost a blind loyalty to your master. In the Book of Rites, something similar to chūshin gishi is mentioned which is called zhongchen yishi. Interpretations of the passage from the Book identified those who would sacrifice themselves in the name of duty should live on idealized. However, there were also those such as Ogyū Sorai, that agreed on condemnation of the rōnin as criminals. Sorai, Satō Naokata, and Dazai Shundai were some of those who believed that the rōnin were merely criminals and murderers with no sense of righteousness, since they did violate the law by killing Kira Yoshinaka. So definitely there was controversy revolving around the legitimacy of the rōnins' actions.

Confucianism and the deification of the rōnins collision is something that is very important to the way to understanding Bakufu law. Confucian classics and the Bakufu law may have seemed to complement each other to allow revenge. Hayashi Hōkō claims that the idolization of the rōnin may have been allowed because their actions matched with the Chinese loyalists. Also suggesting that only by killing themselves would they be able to claim their title as chūshin gishi. Hokō summarized that there might have been a correlation between the law and the lessons put forth in Confucian classics.