The incredible story of Jules Brunet, the French military leader who fought with the samurai

On 2 January 1838, Jules Brunet was born in the fortified town of Belfort, where the military had a significant impact on daily life.

As the son of a veterinarian in the French army, he grew up with firsthand exposure to military institutions, technical skills, and national service.

Apparently, he displayed early strengths in mathematics, sketching, and scientific reasoning. 

By his late teens, Brunet had secured admission to the École Polytechnique in Paris, a highly competitive institution that trained engineers, scientists, and military officers for state service.

His instructors described him as methodical and precise in technical matters and tireless in his efforts.

After he had graduated in 1859, he transferred to the École d’Application de l’Artillerie et du Génie in Metz, where he began specialising in artillery science.

Soon after his commission in 1861, his superiors assigned him to a mapping and surveying role, which suited his careful nature.

In 1862, French military leadership sent him to Mexico as part of Emperor Napoleon III’s expeditionary force, where he supported artillery operations during the campaign to install Archduke Maximilian of Austria as Emperor of Mexico. 

During the Mexican campaign, he earned the Légion d’Honneur after he had produced reliable artillery positions under pressure and had conducted effective fire missions that supported French advances.

At the Siege of Puebla in 1863, he applied standard techniques with impressive accuracy under fire.

His ability to adapt technical training to field conditions often made him a valued asset in a politically sensitive war zone. 

By the mid-1860s, Brunet had returned to France and resumed work at the Ministry of War.

At that time, Japan’s Tokugawa Shogunate formally requested French assistance to modernise its army and, in response, the French government dispatched a small team of military instructors, known as the Mission Militaire Française au Japon.

Officials selected Brunet as one of the key artillery experts for this mission, alongside other officers, including cavalry specialist Captain André Cazeneuve and interpreter Charles Marlin. 

Upon his arrival in Yokohama in 1867, Brunet joined the French mission under Captain Charles Chanoine and began training elite Shogunate troops.

He travelled to Shizuoka, where he taught advanced techniques in artillery positioning, fortification, and logistics.

His ability to translate European tactical manuals into usable training systems earned him praise from Japanese officers. 

At that stage, many of his students were samurai by birth but unfamiliar with modern battlefield techniques.

Brunet maintained a high standard of discipline and clear instruction, which gained the trust of both rank-and-file soldiers and senior Tokugawa commanders.

He specifically worked closely with Ōtori Keisuke, who was commander of the elite Denshūtai unit and a key figure in the Shogunate’s efforts to resist imperial reform. 

Importantly, Brunet inspected fortifications, supervised field exercises, and built relationships based on mutual respect and shared goals.

He understood the political tension that had built around the Shogunate but remained focused on his duties as a military professional. 

Early in 1868, the Boshin War began after imperial loyalists declared the restoration of Emperor Meiji.

Fighting broke out near Kyoto, and the Tokugawa forces suffered an early defeat at the Battle of Toba-Fushimi.

French policy required immediate neutrality, and the mission was ordered to withdraw. Brunet, however, refused to leave. 

Instead of returning to France, he resigned his commission and remained with the Tokugawa loyalists, with who he travelled north with Enomoto Takeaki, a naval commander who led thousands of Shogunate troops to Hokkaido, where they aimed to establish a separate republic.

Brunet agreed to assist with the military structure of what became the short-lived and unrecognised Republic of Ezo, which was a unique political experiment and the only attempt to establish a republic on Japanese soil during the nineteenth century. 

He organised the army into corps-style units and trained the forces largely in French methods.

Each Japanese officer received training based on Napoleonic doctrine, and Brunet helped fortify Goryōkaku, which had been built to a star plan by European engineers during an earlier phase of reform.

There, he oversaw artillery operations and directed fire missions with calm authority.

During the Battle of Hakodate between 4 and 27 May 1869, Brunet worked alongside Ōtori and other Japanese commanders to coordinate the final defence of Ezo.

As imperial troops closed in, he remained at his post until resistance collapsed.

Japanese leaders spared him from punishment, and he ultimately surrendered to French diplomats, who negotiated his return home. 

Following the defeat, Brunet’s future depended on political caution, as his involvement in the conflict embarrassed the French government, which had already recognised the new Meiji regime.

French officials feared that taking legal action against him would cause more tension because Napoleon III remained in power and wished to avoid complicating diplomatic ties with Japan, so they allowed him to return on condition of silence and cooperation.

Upon his arrival in France later that year, he submitted a full report to the Ministry of War, which described the organisation, personnel, and strategies used by the Tokugawa loyalists.

He explained his decision to remain in Japan and justified his actions as consistent with honour and loyalty to those he had trained.

The government, unwilling to draw attention to the affair, apparently chose not to court-martial him. 

Shortly after, France declared war on Prussia, and Brunet was recalled to active service in July 1870 and fought in several engagements during the Franco-Prussian War.

During the 1870s and 1880s, Brunet advanced through senior artillery positions, gradually took charge of strategic planning and inspection, and oversaw the education of officers.

He received regular praise for his work in standardising artillery training and improving the accuracy of gunnery procedures across several regions of the French army. 

He had attained the rank of général de division by 1891 and thereafter oversaw military operations across several regions.

His colleagues regarded him as reliable in conduct and exact in technical detail, and steady under pressure.

He avoided politics and did not write or speak publicly about his time in Japan, even though the episode had attracted public interest by the end of the century. 

By the time of his death in 1911, Jules Brunet had secured a full career in the French military despite his defiance during the Boshin War.

His decision to stay with the Tokugawa cause had not prevented him from receiving promotions or fulfilling his duties at home.

His life was split between two hemispheres and two worlds, which continues to be one of the most remarkable meetings of samurai honour and European artillery accuracy ever recorded.

He never published memoirs, and Brunet's story, which inspired later generations, is widely thought to have partly inspired the fictional character of Nathan Algren in the 2003 film The Last Samurai.