Henri-Etienne Bretonnet (1864–1899) was a French naval officer, killed with most of his men in the battle of Togbao.
Bretonnet entered in the navy by attending the École Navale, the Navy Academy in charge of the education of the officers of the French Navy. Among his first important mission was the participation in the second Mizon Mission in 1892; the expedition was commanded by lieutenant de vaisseau Louis Mizon, who under him Albert Nebout and Bretonnet as enseigne de vaisseau.
The expedition, that was to cover the territories between the Niger River and the Adamawa, was primarily designed to carve a French enclave on the Benue River in Northern Nigeria, a territory that the British claimed being theirs following the Berlin Conference. Ignoring the protests of the Royal Niger Company that Adamawa had been given to the British by the Berlin Conference, he hoisted the French flag in the region after a treaty with the Emir of Muri; unsupported by France, he was forced to leave the area with his men in 1893.
In 1896, Bretonnet, by now promoted lieutenant, was given command of an expedition meant to establish French control on the navigable portions of the Niger River below Bussa, in modern Nigeria. These plans were opposed by the Royal Niger Company, claiming the English had already treaty rights on the region.
Bretonnet left the French post of Carnotville, in Dahomey, on December 28, 1896 and headed north, penetrating in the region of Borgu. Bretonnet passed by Kandi and entered in Illo, where he placed a Resident; then, pointing south, he arrived at Bussa, whose emir Kisan Dogo was involved in a bitter feud with Kibari, ruler of Wawa, that supported a rival claimant to the throne of Bussa. In exchange for the promise of helping Kisan Dogo in removing Kibari and replacing him with a relative of his, Bretonnet held Bussa "in the name of the French Republic" claiming to "occupy effectively the territory of Bussa".