First Chōshū Expedition

From the 7th month through the 12th month of Genji 1 (1864) (lunisolar calendar), the Edo shogunate launched a large-scale military punitive campaign against the Chōshū Domain. This is called the First Chōshū Expedition. This expedition mobilized 35 domains and roughly 150,000 troops. It was a major military demonstration of shogunal power in late Edo history, yet it ended bloodlessly through the skillful mediation of Saigō Takamori, without a single battle being fought.

The Kinmon Incident and the Background to the Punitive Expedition

The direct trigger for the punitive expedition was the Kinmon Incident (Hamaguri Gate Incident), which broke out on the 19th day of the 7th month of Genji 1 (20 August 1864). The radical faction of Chōshū (sonnō jōi radicals) had vowed revenge even after being driven out of Kyoto in the coup of the 18th day of the 8th month of Bunkyū 3 (1863) the previous year. Chōshū troops led by Kusaka Genzui and Kijima Matabei entered the capital and fired toward Hamaguri Gate of the Imperial Palace, which was guarded by Satsuma and Aizu forces. Firing on the Imperial Palace constituted high treason against the court, and the Chōshū forces were repulsed by a combined force of Aizu, Satsuma, and Kuwana. Both Kusaka Genzui and Kijima Matabei died in battle, and Chōshū's prestige plummeted.

Four days after the Kinmon Incident, on the 23rd day of the 7th month, the imperial court issued an imperial edict to the shogunate ordering the suppression of Chōshū. The shogunate seized this opportunity, appointed Tokugawa Yoshikatsu of the Owari Domain as commander-in-chief of the punitive expedition (seichō sōtoku), and ordered the domains to take part. The final number of participating domains was 35, and the army is said to have numbered about 150,000. This scale of mobilization was unprecedented throughout the Edo period and was a symbol of the shogunate's authority over the domains.

Link with the Four-Nation Allied Fleet Bombardment of Shimonoseki

While the First Chōshū Expedition was in progress, in the 8th month of Genji 1 (1864), the Four-Nation Allied Fleet of Britain, France, the Netherlands, and the United States bombarded Shimonoseki in retaliation for Chōshū's attacks on foreign ships the previous year (the Shimonoseki War, the expulsion-policy attacks of Bunkyū 3 (1863)). This Four-Nation Allied Fleet bombardment of Shimonoseki (Bakan War) destroyed all of Chōshū's batteries, and Chōshū was forced to pay an indemnity of 3 million dollars (later taken over by the shogunate). Caught in a pincer from within and without, Chōshū was militarily much weakened.

Saigō Takamori's Mediation and the Bloodless Conclusion

As the shogunate's punitive army closed in on Chōshū, Saigō Takamori of the Satsuma Domain, who had joined as a strategist of the punitive expedition, turned his attention to the submission faction (conservative faction, zokuron-ha) within Chōshū. Within the Chōshū Domain, a backlash against the sonnō jōi radicals (loyalist faction, seigi-ha) arose following the defeat at the Kinmon Incident, and the submission faction, led by Mukunashi Tōta and others, was gaining the upper hand. As a way to avoid actually carrying out the punitive campaign, Saigō sought a settlement in the form of Chōshū's “apology and submission.”

As a result of negotiations, the Chōshū Domain accepted three conditions demanded by the shogunate: (1) seppuku of the three senior councillors (Kunishi Shinano, Masuda Uemonnosuke, and Fukuhara Echigo), who were regarded as the leaders of the Kinmon Incident; (2) beheading of four staff officers (Shishido Samanosuke, Takeuchi Shōbei, Nakamura Kurō, and Sakuma Sahei); and (3) transfer of the five court nobles (gokyō), who were court nobles favoring sonnō jōi, from Yamaguchi to other domains. In the 11th month of Genji 1 (December 1864), the three senior councillors committed seppuku. In the 12th month, the domain lord and his son submitted letters of apology, and on the 27th day of the 12th month of Genji 1 (24 January 1865), the punitive army was disbanded.

However, this bloodless conclusion did not truly subdue the radicals of Chōshū. The remnants of the loyalist faction, who had been purged and suppressed by the conservative faction, made a comeback after Takasugi Shinsaku led the Rikishitai (sumo wrestlers' unit) and Yūgekitai in the Kōzan-ji uprising on the 15th day of the 12th month of Genji 1 (12 January 1865). By the spring of 1865, they had regained control of the Chōshū Domain. Afterwards, Chōshū concluded an alliance with the Satsuma Domain (Satchō Alliance, 1866) and openly resisted the shogunate's Second Chōshū Expedition (1866) with military force.

Impact on Sword Culture and the Military Transformation of the Late Edo Period

The First Chōshū Expedition is also an event that symbolizes the historical turning point of coexistence between swords and modern weapons in the late Edo period. Samurai of the participating domains still marched out wearing their daishō (long and short swords). However, Western-style firearms (Minié rifles and Geweer muskets) were rapidly spreading as the main weapons, replacing matchlock muskets, and the samurai's “sword” grew increasingly symbolic and ceremonial. The fact that the Kiheitai of Chōshū recruited soldiers from commoners and farmers and adopted Western-style training and Western firearms showed that the military system centered on samurai and swords was beginning to collapse.

Ironically, the enormous mobilization power that the shogunate's forces displayed during the expedition accelerated the substantive hollowing out of shogunal authority. The “bloodless conclusion” brought about through Saigō Takamori's mediation made clear in the eyes of the various domains that the shogunate had not militarily subdued Chōshū, but had merely resolved the matter through a political compromise. This spread the perception among the domains, including Satsuma, that “the shogunate was militarily unreliable.” Eventually it prepared the ground for the upheavals of the late Edo period that followed: the Satchō Alliance, the Second Chōshū Expedition, the Return of Political Power to the Emperor (Taisei Hōkan), and the Boshin War.

The First Chōshū Expedition is remembered in Japanese history as a “punitive expedition that mobilized on a large scale yet did not fight a single battle.” However, it was precisely this bloodless ending that symbolized the collapse of shogunal authority. It became one of the turning points that decisively marked the shift from an era of samurai who wore swords to a modern military state.