During the Sengoku period, Oda Nobunaga made sumo a popular sport, aided by the emergence of large cities (like Edo, Osaka, Sendai and Nagoya), which soon began to compete with Kyoto's cultural monopoly, as it was Japan's only metropolis at the time.

[11] During the Edo period, sumo bouts, called kanjin-sumo (勧進相撲), were often held to raise funds to develop provinces (new construction or repair of bridges, temples, shrines and other public buildings) or for entertainment purposes.

[15] On the other hand, a number of rōnin had no choice but to put their martial skills to good use in street sumo tournaments, called tsuji zumō (辻相撲, tsuji-sumo, lit.

[16] Similarly, a number of street entertainment wrestling groups formed and began touring, sometimes with the support of shrines that occasionally recruited them as part of religious festivities and to help priests raising money for the construction of buildings.

[19] Over the next two decades or so, the wrestlers, now without any income, decided to petition the authorities to lift the bans, forming informal associations that resembled coalitions of interests to protect themselves from any violent repression of their movement.

[34] At the same time, political circles were organized to preserve some of Japan's indigenous traditions, saving on behalf of the association the privilege of wrestlers to wear samurai chonmage (topknot) in 1871.

[45][46] Under the impetus of this tournament, a joint competition plan with a common banzuke was proposed, concluding talks that had been taking place since the early 1920s to merge the two rival associations.

[60] Thanks to the efforts of Musashigawa (the former Dewanohana) and Kasagiyama Katsuichi (a wrestler who spoke a little English), the association succeeded in convincing the Americans of the tournaments' good faith, and the first honbasho to be held after the war was in November 1945.

[61] In 1950, following a scandal involving the withdrawal from competition of the three yokozuna of the time (Azumafuji, Terukuni and Haguroyama) the association considered demoting the highest-ranking sumo wrestlers in the event of a poor score or consecutive absence from two tournaments, but decided to back down following pressure from traditionalists and purists.

In 1957, a special commission of the National Diet investigated the improper use of money by the association due to the general inability of the public to reserve seats for tournaments, in opposition to its non-profit status.

[68] More specifically, the case of Hawaiian wrestler Takamiyama in 1976 provoked a conservative reaction from the association, which declared that sumo being Japan's national sport, it was inconceivable that a foreigner could participate as a trainer.

In 1992, a member of the Yokozuna Deliberation Council, Kojima Jo, was quoted in the magazine Bungei Shunjū as opposing the appointment of foreigners, who he felt were too far removed from the hinkaku (品格), the 'dignity', needed to become one of professional sumo's top ranked wrestler.

[76] In a move to increase transparency, the MEXT (under Vice-minister Kenshiro Matsunami) demanded the opening of the Sumo Association's board of directors to external auditors, introducing non-toshiyori personalities into the decision-making system for the first time in 63 years.

[77][78] At the time, the association's statutes clearly stated that only former wrestlers could sit on the board of directors but Vice-minister Matsunami insisted that the scandal was "the biggest disgrace in the history of sumo".

[84] At one point, the revelation of collusion between wrestlers and yakuza was such that MEXT threatened to dissolve the association's public non-profit institution act and confiscate the JSA's properties, including the Ryōgoku Kokugikan.

[81] At the time, the association was involved in negotiations with the ministry to bring its statutes into line with the requirements of a law on public establishments passed in 2008, initially with the aim of achieving this status by the end of November 2013.

[91] In November 2015, the chairman of the association, Kitanoumi, passed away and an official funeral was held at the Ryōgoku Kokugikan by the JSA in December under the chairmanship of Hakkaku (former Hokutoumi), with around 2,500 people attending.

This occurred after the Cabinet Office issued a recommendation urging the Japan Professional Sports Association to reform its internal organization, which was inadequate to supervise other public interest incorporated foundations.

[105] In 2022, for the first time in its history, the association signed a partnership agreement with a local government, Sumida Ward, to revitalize the district by encouraging sumo wrestlers to visit schools, and promote sport and tourism.

[107] In addition, the association was criticized for managerial problems, which led to moral harassment[clarification needed] and the suspension of three administrative executives in September, without the situation changing according to the daily Nikkan Sports.

[123] An exception to the normal acquisition is made for the most successful rikishi, with era-defining yokozuna being offered a "single generation" or "lifetime" elder stock, called ichidai toshiyori (一代年寄).

In 2010, the Japan Sumo Association announced its decision to dismiss Ōzeki Kotomitsuki and Ōtake (former Takatōriki), for betting on baseball games in a gambling ring run by the yakuza.

[172] Sumo Association chairman Hanaregoma declared in August 2010 that "violent groups or antisocial forces" were being banned from accessing tournament venues, training stables and other facilities.

The controversy arose when The Nihon Keizai Shimbun reported that Samoan-born ōzeki Konishiki had alleged racial discrimination was the reason for him being denied promotion to sumo's top rank of yokozuna.

A hazing scandal was exposed in which a Tokitsukaze stable's 17-year-old sumo trainee died after a serious bullying incident involving his stablemaster Jun'ichi Yamamoto hitting him on the head with a large beer bottle and fellow rikishi being subsequently ordered to physically abuse him further.

[181] Violence affairs also came up to light in 2017, when Japanese newspaper Sports Nippon reported that Yokozuna Harumafuji had assaulted fellow Mongolian wrestler Takanoiwa during a regional sumo tour in Tottori in late October.

[187] In March 2023 a former lower-ranked wrestler in Sadogatake stable, Daisuke Yanagihara, sued the Japan Sumo Association and his former stablemaster (ex-Kotonowaka) on allegations that he was forced to quit the sport.

Yanagihara claimed that his human rights were violated and that, during the COVID-19 pandemic when the Sumo Association instituted health protocols, he was denied his request to sit out of the January 2021 tournament over fears of contracting the virus following cardiac surgery.

The channel offers light-hearted and humoristic videos, such as a golf competition between former yokozuna Hakuhō, Kisenosato and Kakuryū or chankonabe receipes with small skits featuring low-ranking wrestlers.

In August 2022, the association launched an English-language YouTube channel called Sumo Prime Time in hopes of drawing a larger international audience to the sport.