Ōshio Heihachirō's Rebellion

On the 19th day of the 2nd month of Tenpō 8 (February 19, 1837), in Osaka (present-day Osaka City), Ōshio Heihachirō, a former yoriki (mid-level samurai assisting the magistrate) of the Osaka Eastern Town Magistrate's Office, rose in rebellion alongside his disciples and commoners. Inscribed in history as one of the largest urban uprisings of the Edo period and as a collision between the contradictions of feudalism and the conscience of a samurai, this incident holds important significance from the perspective of the Japanese sword and samurai spirituality as well.

Ōshio Heihachirō (1793–1837) devoted himself for many years to his duties as a yoriki at the Osaka Eastern Town Magistrate's Office. He was also renowned as a scholar of Yōmeigaku (the practical Confucianism of Wang Yangming) and established a private academy called the Senshin-dō, where he educated many disciples. The core of Yōmeigaku is the concept of chigyō-gōitsu — that knowledge and action are one — emphasizing practical morality rather than mere scholarship. Ōshio was a man who sought to embody the spirit of this philosophy to its fullest extent.

The Tenpō Famine (1833–1839) brought nationwide crop failures, causing many deaths by starvation, particularly in rural areas. In Osaka, too, prices soared and the lives of the poor deteriorated to an extreme degree. Even after retiring from the magistrate's office in 1830, Ōshio could not turn a blind eye to their suffering, selling his book collection to provide relief to the starving poor. However, the shogunate and the magistrate's office were reluctant to provide famine relief, reasoning that Osaka was a prosperous commercial city with considerable accumulated wealth. The great merchants, rather than aiding the destitute in their midst, were only too willing to ship rice to Edo at the shogunate's behest, indifferent to the people suffering from hunger before their eyes.

Ōshio attempted to petition against the corruption of the magistrate's office, but his appeals were rejected. Concluding that the path of reform through legal means was closed, he became convinced, in accordance with the philosophy of chigyō-gōitsu, that taking action itself was a moral imperative. Around Tenpō 7 (1836), he began planning an uprising, recruiting like-minded disciples, and devised a scheme to burn down the homes of great merchants, seize their hoarded rice and gold, and distribute them to the poor.

On the eve of the uprising, the plan was betrayed to the magistrate's office by an informant, and Ōshio advanced his timetable, rising in revolt in the early morning of the 19th day of the 2nd month of Tenpō 8. Raising a banner reading "Save the People" (kyūmin), the rebels opened fire with cannons and set fires; flames spread throughout central Osaka, and approximately one-fifth of the urban area was said to have burned down. However, the shogunate forces and the magistrate's office suppressed the rebellion swiftly, and the uprising was crushed in just over half a day. Ōshio and his son Kakunosuke continued to flee, but on the 27th day of the 3rd month, the townhouse where they were hiding was discovered. Cornered, Ōshio detonated explosives and perished in the blast; Kakunosuke also took his own life the same day.

As an aftermath, harsh punishment was meted out to surviving participants and those involved. Many were executed by crucifixion, beheading, or sentenced to exile. Moreover, despite Ōshio being already dead, the shogunate carried out the extraordinary sentence of "posthumous crucifixion" — crucifying his corpse — demonstrating how much shock and threat the shogunate felt from this rebellion.

Why does Ōshio's Rebellion hold important significance from the perspective of the Japanese sword and samurai culture? First, Ōshio himself was a samurai (a yoriki), a man of the class permitted to wear swords. In the Edo period, the samurai's duty lay in loyalty to one's lord and the shogunate and in the maintenance of order; yet Ōshio placed his moral mission to "save the people" above his loyalty to the shogunate. This represents an instance of deploying the bushidō concept of gi (righteousness and moral duty) as a critique of the established order, symbolizing an ideological shift in which the sword could be not merely a symbol of authority but also a tool for the people.

Second, Ōshio's Rebellion exerted profound influence on the loyalist activists of the late Edo period as an event expressing through force the terminal contradictions of the feudal system. Thinkers and revolutionaries of the bakumatsu era, including Yoshida Shōin and Saigō Takamori, demonstrated strong resonance with Ōshio's actions. The Yōmeigaku concept of chigyō-gōitsu that Ōshio employed shares ideological continuity with the "Revere the Emperor, Expel the Barbarians" (sonnō jōi) movement of the late Edo period, and is considered one of the spiritual foundations that helped form the soil from which the Meiji Restoration grew.

Furthermore, this incident possessed the distinctive characteristic of being a rebellion led by a samurai in Osaka, a commercial city. The fact that it occurred in an urban area rather than a rural one, and was led by a former samurai rather than peasants, symbolizes the depth of social contradictions during the Tenpō era. The impact of Ōshio's Rebellion spread throughout the country; in the same year, in Kashiwazaki, Echigo Province (present-day Kashiwazaki City, Niigata Prefecture), Ikuta Yorozu, a scholar of national learning, responded to Ōshio's Rebellion by attacking the Kuwana Domain's Kashiwazaki garrison, and similar chain reactions were seen in various regions.

Ōshio Heihachirō's Rebellion holds a permanently special place in Japanese history, intellectual history, and the cultural history of the sword, as an incident in which, at a time when Edo shogunate rule was becoming less than absolute, a single samurai took up the sword and cannon in devotion to his convictions.