He was born at Fukui village in Tosa, today's Kochi, into a family of shirafuda, the highest rank of country samurai. His name was Kotate and his pen name Zuizan. In Tosa the gap between upper samurai and country samurai was wide, and it would cast a shadow on his later work.
Around this time he lost both parents in quick succession and, while supporting his grandmother, married Shimamura Tomiko. The couple was very close, and when Hanpeita was later in prison, Tomiko is said to have kept to a frugal life out of concern for him.
Having mastered the Itto-ryu and other styles, he opened a fencing school in Kochi's castle town. Many young country samurai gathered, including Nakaoka Shintaro and Okada Izo. He was revered both as a sword master and as a leader who united the young by his character.
He went to Edo, entered the Shigakukan, the Kyoshin Meichi-ryu school of Momoi Shunzo, and soon became its head student. In Edo he mixed with samurai from many domains and felt the currents of the times. These experiences turned his eyes to national politics.
In Edo he mixed with Kusaka Genzui of Choshu and Satsuma samurai and deepened his revere-the-emperor, expel-the-barbarians views. Back in Tosa he founded the Tosa Loyalist Party and became its leader. Sakamoto Ryoma joined early, and some two hundred, mostly country samurai, are said to have signed.
Yoshida Toyo, the domain strongman who favored opening the country, was killed by members of the Loyalist Party. Hanpeita is said to have been involved, and domain policy then leaned toward revering the emperor and expelling foreigners. He went up to Kyoto with the lord Yamauchi Toyonori.
In Kyoto he mixed with courtiers and activists of many domains, and when the imperial envoy Sanjo Sanetomi and others went to Edo to press the shogunate to expel foreigners, he joined the escort. Though a country samurai, he stood on the political stage between court and shogunate, and his name became known nationwide.
The domain raised him to upper-samurai rank and gave him a post handling its relations in Kyoto, a rise across the status barrier. But the former lord Yamauchi Yodo was deeply displeased with the Loyalist Party's haste and Toyo's assassination.
The coup of the eighteenth day of the eighth month drove loyalist courtiers and Choshu from Kyoto. As the tide turned, Yodo cracked down on the Loyalist Party, and Hanpeita was arrested in Tosa and imprisoned. In prison he kept writing letters thinking of his comrades.
After about a year and a half of interrogation, he was ordered by the domain to commit seppuku and quietly fulfilled it, ending his life at 35. He was later honored by the Meiji government, and his ideals are long remembered in his native Kochi.
Yoshida TōyōSakamoto RyōmaNakaoka ShintarōKusaka GenzuiSanjō Sanetomi
Oguri TadamasaYamauchi Yōdō (Toyoshige)Saigō TakamoriMatsudaira Shungaku (Yoshinaga)Yoshida ShōinKiyokawa HachirōKondō IsamiHashimoto Sanai
People of the Edo period ・ People by period
Based on facts found in textbooks and biographies. Uncertain points are marked as such.