The Aburanokōji Incident

Itō Kashitarō's Enlistment and the Split of the Goryō Eishi

Itō Kashitarō was a swordsman of the Hokushin Ittō-ryū school and an erudite activist who had run a dojo in Fukagawa, Edo, during the Bunkyū era. In 1864 (Genji 1), he accepted recruitment by Kondō Isami, who was seeking to expand the Shinsengumi's ranks, and joined the group along with disciples including Tōdō Heisuke, taking the senior post of staff officer (sanbō). Itō was known as a theorist well versed in kokugaku (national learning) and military science, commanding respect within the Shinsengumi. But unlike the pro-shogunate leanings of the Shinsengumi as a whole, Itō held strong sonnō tōbaku (imperial restoration / anti-shogunate) convictions, and his differences with commander Kondō Isami grew increasingly serious over time.

In the third month of 1867 (Keiō 3), Itō and a dozen-odd followers broke away from the Shinsengumi and formed the Goryō Eishi ("Guardians of the Imperial Mausoleum"), nominally tasked with protecting the tomb of the late Emperor Kōmei. Based at Gessshin'in, a sub-temple of Kōdai-ji, the group was also known as the "Kōdai-ji Party." They are said to have maintained contact with Satsuma domain while pursuing their own anti-shogunate activities. The Shinsengumi and the Goryō Eishi maintained an outward appearance of cordial relations while, beneath the surface, tensions simmered as each side sent agents to spy on the other.

The Volatile Political Climate Around the Restoration of Imperial Rule

The Aburanokōji Incident occurred in the eleventh month of Keiō 3, shortly after Shogun Tokugawa Yoshinobu formally offered to return political authority to the imperial court (Taisei Hōkan) on the 14th day of the tenth month — an unprecedented political transformation. The Imperial Restoration Proclamation would follow just ten days after this incident, on the 9th day of the twelfth month, meaning Kyoto was in the midst of its most tense standoff yet between shogunate and anti-shogunate forces. Against this backdrop, the Goryō Eishi's growing ties to the anti-shogunate camp appeared as an intolerable threat to the pro-shogunate Shinsengumi and Aizu domain.

Kondō and Hijikata's Decision to Purge

The Shinsengumi had reportedly planted Saitō Hajime within the Goryō Eishi as an informant. Based on Saitō's reports, Kondō and Hijikata are said to have received word that Itō was conspiring with Satsuma domain to assassinate Kondō — though later research has cast doubt on whether such an assassination plot genuinely existed, and no conclusive confirmation has emerged. Regardless, Kondō and Hijikata came to regard Itō as a dangerous political rival and settled on a policy of eliminating the Goryō Eishi by force. For Kondō and Hijikata, who already had the precedent of the internal purge of Serizawa Kamo in 1863, eliminating a senior figure with conflicting political leanings by force was, by this point, an established organizational tactic.

Saitō Hajime had been a trusted member of the Shinsengumi since joining in 1864, and while he appeared to have defected alongside Itō when the Goryō Eishi was formed, he is said to have actually been operating as an informant for the Shinsengumi throughout. This double-agent role remains a frequently noted episode in later Shinsengumi scholarship, illustrating one facet of espionage and covert surveillance in the bakumatsu period. It has also been noted that, around the time this purge was being planned, the Shinsengumi's headquarters had already relocated from Mibu to Nishi Hongan-ji and then to Fudōdō-mura, a period in which the group was strengthening its organizational structure while heightening vigilance against hostile outside forces.

The Assassination — The Ambush at Aburanokōji

On the night of the 18th day of the eleventh month of Keiō 3 (December 13, 1867), Itō Kashitarō was invited to the residence of Kondō Isami's mistress and lavishly entertained with food and drink, reportedly as part of a plan to lower his guard before striking him on his way home. On his return route, near Aburanokōji-Shichijō in Kyoto, Shinsengumi member Ōishi Kuwajirō and others, acting on Hijikata Toshizō's orders, ambushed and attacked Itō. Itō drew his sword and fought back, but was severely wounded in the first blow and died soon after. The Shinsengumi left Itō's body where it lay, carrying out a plan to lure in Goryō Eishi comrades who would come to retrieve it, so as to wipe them out in a single stroke.

Itō's body was left in the street at Aburanokōji, and Goryō Eishi comrades who learned of the incident rushed to the scene that night to recover it. The plan succeeded: seven Goryō Eishi members, including Tōdō Heisuke, Hattori Takeo, and Mōnai Arinosuke, who came to the site, were ambushed by waiting Shinsengumi members. In the ensuing melee, Tōdō Heisuke, Hattori Takeo, and Mōnai Arinosuke were killed, while some of the others escaped and were reportedly given protection at the Satsuma domain residence. Accounts of the number of Shinsengumi participants vary from as few as 17 to as many as 40-50, and the exact roster remains unconfirmed. Tōdō Heisuke had once studied alongside Kondō and Hijikata at the Shieikan dojo as a fellow founding member, and the fact that he was killed by men he had once called comrades is often cited as emblematic of the incident's character as an internal feud. Hattori Takeo and Mōnai Arinosuke were likewise key members of the Goryō Eishi, and their deaths cost the group most of its fighting strength in a single night.

Aftermath and the Dissolution of the Goryō Eishi

The Aburanokōji Incident is notable for its character as a calculated betrayal deliberately engineered by the Shinsengumi, and is regarded as one of the most carefully premeditated purges of the bakumatsu era. The incident effectively destroyed the Goryō Eishi, and its surviving members went on to throw themselves into the anti-shogunate movement under Satsuma domain's protection. This was the Shinsengumi's last large-scale internal purge, and it came just before the tumultuous events that would lead to the Battle of Toba-Fushimi and the ultimate dissolution of the Shinsengumi itself. In the first month of 1868 (Keiō 4), the Shinsengumi fought as former-shogunate forces at the Battle of Toba-Fushimi and were routed; commander Kondō Isami was captured and beheaded by imperial forces not long after, and vice-commander Hijikata Toshizō was killed in action the following year, 1869, at the Battle of Hakodate. The Aburanokōji Incident is regarded as the prelude to this final phase of the Shinsengumi's collapse.

Figures and Swords Associated with the Incident

Itō Kashitarō was a swordsman trained in the Hokushin Ittō-ryū school, and was also known as a scholarly figure versed in kokugaku and military science. Tōdō Heisuke was one of the few founding Shinsengumi members to break away with Itō, and formed the core of the Goryō Eishi. Hijikata Toshizō, who is said to have directed the Shinsengumi's side of the operation, was Kondō's right-hand man and consistently led the group's internal purges and discipline — making the Aburanokōji Incident part of the same lineage of internal purges under the Kondō-Hijikata command structure that began with the assassination of Serizawa Kamo. Reliable records of the specific swords used by individual participants are scarce, but this was an era in which swordsmen of various schools — Hokushin Ittō-ryū, Tennen Rishin-ryū, and others — clashed with combat-grade blades throughout bakumatsu Kyoto, and the Aburanokōji Incident is remembered as one emblematic episode of this broader pattern of swordsman-versus-swordsman conflict in the city. The Goryō Eishi's base, Gesshin'in, remains today a sub-temple of Kōdai-ji, and the fact that Itō and his followers used it as a base for contacts with anti-shogunate allies illustrates how Kyoto's temples could also serve as cover for political activity in the bakumatsu period.

Historical Significance

The Aburanokōji Incident holds an important place in bakumatsu historiography as a symbolic case in which ideological conflict within the Shinsengumi — over whether to support the shogunate or the restoration of imperial rule — escalated into armed violence. The purge cost the Shinsengumi a capable figure in Itō Kashitarō; while it restored internal discipline in the short term, it is also assessed as having driven away talent and contributed to the group's growing organizational rigidity over the longer term. The area around Aburanokōji-Shichijō in Kyoto, where the incident took place, still preserves memorial markers to Itō and his fellow Goryō Eishi members, keeping alive the memory of the ideological conflicts and sacrifices among bakumatsu-era activists. Occurring amid the rapid political upheaval between the Taisei Hōkan and the Imperial Restoration, this purge stands as more than an internal Shinsengumi feud — it also encapsulates the broader tension between pro-shogunate and anti-shogunate forces in Kyoto during the final days of the bakumatsu era.