The Kōzanji Uprising

Background — The Kinmon Incident, the Shimonoseki War, and the First Chōshū Expedition

In 1864 (Genji 1), Chōshū domain suffered defeat at the Kinmon Incident in Kyoto and was branded an enemy of the court, and was further crushed by the combined fleets of Britain, France, the United States, and the Netherlands in the Shimonoseki bombardment (the Bakan War), leaving the domain reeling from blows on multiple fronts. The shogunate seized the opportunity to launch the First Chōshū Expedition, surrounding the domain with a punitive force said to number 150,000.

Facing this unprecedented crisis, a conservative faction within the domain favoring submission to the shogunate — the so-called "junronha" — rapidly gained power. Led by figures such as Mukunashi Tōta, the junronha seized control of domain policy, holding the three senior councilors Kunishi Shinano, Masuda Uemonnosuke, and Fukuhara Echigo responsible for the Kinmon Incident and ordering their seppuku, while executing four staff officers as well. Prominent figures of the reformist faction, who had long championed reverence for the emperor and the expulsion of foreigners, were also imprisoned and executed one after another, driving the reformist faction to the brink of annihilation. Chōshū outwardly submitted to the shogunate in an attempt to deflect the punitive expedition.

The Uprising at Kōzan-ji

Amid these circumstances, Takasugi Shinsaku, a central figure of the reformist faction, had been quietly watching for an opportunity to overthrow the junronha government. On the night of the 15th day of the 12th month of Genji 1 (January 12, 1865), Takasugi visited Sanjō Sanetomi and the other "Five Nobles" who were sheltering at Kōzan-ji temple in Chōfu (present-day Shimonoseki), and declared his intent to rise in revolt, riding off on horseback through the snow to launch his uprising.

At this point, only 84 men followed Takasugi. The force consisted of the Rikishi-tai (sumo wrestler corps) under Itō Hirobumi (then known as Itō Shunsuke), the Yūgeki-tai (guerrilla corps) under Ishikawa Kogorō (later known as Mihori Kōsuke), and volunteers drawn from the surrounding populace. The following day, the 16th, the rebels attacked and seized the Chōshū domain's magistrate's office at Bakan (Shimonoseki), attempting to capture the domain's warships as they began direct action against the junronha government.

The Militia Units Join and the Battles of Edō and Ōta

At first, the domain's various militia units based in Yamaguchi — the Kiheitai, Mitate-tai, Yūgeki-tai, and others — avoided direct confrontation with the junronha government and maintained a posture of submission. However, as the junronha government continued executing reformist leaders, anger rapidly spread among the militia units. On the 5th day of the 1st month of Genji 2 (1865), the units finally resolved to engage the domain government's forces at Isa. The Battle of Edō, fought from the 5th to the 6th, ended in victory for the rebel militias over the domain government troops. In the fighting at Ōta on the 10th, the rebel side likewise gained the upper hand.

Takasugi Shinsaku joined the main body of militia forces at Isa on the 14th, unifying the previously separate chains of command. On the 16th, at Akamura, the rebels defeated the vanguard of the domain government's forces under Awaya Tatewaki, continuing their string of victories across the domain.

The Fall of Hagi Castle and the Collapse of the Junronha Government

Having won battle after battle, the rebel forces finally seized Hagi Castle, seat of the domain government, on the 14th day of the 2nd month of Genji 2. The leaders of the junronha government fled or were driven from power, and control of domain policy passed into the hands of the reformist faction. What had begun as an uprising of just 84 men at Kōzan-ji had, after roughly two months of fighting across the domain, fundamentally transformed Chōshū's entire political order.

Aftermath — The Shift in Chōshū Policy and the Road to Overthrowing the Shogunate

Having seized control of domain policy, the reformists adopted a stance of outward submission to the shogunate while quietly arming for a future confrontation — a policy of "armed compliance." This shift led directly to Chōshū's armed resistance in the Second Chōshū Expedition the following year (1866), to the Satchō Alliance brokered in part by Sakamoto Ryōma, and to Chōshū's leading role in the anti-shogunate movement during the Boshin War that began in 1868.

Takasugi Shinsaku's decision at Kōzan-ji — launched with a mere 84 followers — fundamentally reshaped the policy of the entire Chōshū domain and ultimately influenced the course of the Meiji Restoration itself, securing its place as one of the most dramatic episodes of the late Tokugawa period. The uprising is remembered as the "Kaiten Gigi" ("the righteous uprising that turned the tide of history") and stands as one of the greatest achievements of Takasugi Shinsaku's life.

Sites That Survive Today

Kōzan-ji temple in Chōfu, Shimonoseki, Yamaguchi Prefecture, where the uprising began, today houses an equestrian statue of Takasugi Shinsaku and remains a popular destination for those touring sites associated with the Bakumatsu era. Interpretive panels within the temple grounds recount the events of the uprising, drawing many visitors interested in the history of the late shogunate and the Meiji Restoration. Kōzan-ji itself is an ancient temple said to have been founded during the Kamakura period, its main hall designated a National Treasure — but in the history of the Bakumatsu era, it is remembered above all as the stage where Takasugi Shinsaku, with only a handful of companions, lit the fuse that would ultimately transform Chōshū's course.