Jules Brunet (2 January 1838 – 12 August 1911) was a French military officer who served the Tokugawa shogunate during the Boshin War in Japan.

Originally sent to Japan as a horse artillery instructor with the French military mission of 1867, he refused to leave the country after the shōgun was defeated, and played a leading role in the separatist Republic of Ezo and its fight against forces of the Meiji Restoration.

[1] As a sub-lieutenant[2] in the horse artillery regiment of the Imperial Guard, he served with distinction throughout the war, particularly during the Siege of Puebla in 1863, for which he was awarded by Emperor Napoleon III with the Cross of the Légion d'honneur.

[2] During his time in Mexico, Brunet was able to create a number of quickly-drawn croquis, many of which were then published by French newspapers to illustrate the war.

He was notably recommended to Napoleon III by government official Émilien de Nieuwerkerke, who also noted Brunet's drawing skills and his "most great desire to be in charge of a military mission to Japan".

He resigned from the French army on 4 October, informing Minister of War Adolphe Niel of his decision in a letter:[1] "I have the honor of presenting to you my resignation from the rank of captain; I declare that from this 4 October 1868, I renounce the prerogatives of the position of artillery officer in the French army".In another letter, to Napoleon III himself, Brunet explained the plan of the alliance, as well as his role in it:[3] "A revolution is forcing the Military Mission to return to France.

After that Imperial victory, Brunet, Cazeneuve and the Shogun's Admiral, Enomoto Takeaki, fled to Edo (now Tokyo) on the warship Fujisan.

[4] There they quickly captured the port city of Hakodate, on 26 October 1868, and by the end of the year Enomoto and his allies had proclaimed the independent Republic of Ezo.

In an interesting postscript to his involvement in the Boshin War, Brunet spoke highly of Shinsengumi vice-commander Hijikata Toshizō in his memoirs.

After receiving a light sentence in his country[5] of suspension for six months, Brunet rejoined the French army in February 1870, with only a slight loss in seniority.

[1] In the aftermath of the war Brunet played a key role as a member of the Versailles Army in the suppression of the Paris Commune.

In 1898, Chanoine, his former senior officer in the Japan mission, by then Minister of War, made Brunet his chef de cabinet and promoted him to general of division.

Through Enomoto's influence, the Imperial government not only forgave Brunet's actions but awarded him medals in May 1881 and again in March 1885, among those the Order of the Rising Sun.