Henri Delannoy

[1][2][3] Delannoy grew up in Guéret, France, the son of a military accountant.

[3] He served as a lieutenant in the French artillery in the Second Italian War of Independence, in 1859, and became a captain in 1863.

He continued to serve in the military, but shifted from the artillery to the supply corps; he served in Africa, became governor of a military hospital in Algeria, participated in the Franco-Prussian War in 1870, and eventually became an intendant in Orléans before retiring in 1889.

His military decorations include the cross and officer's rosette of the Legion of Honour, awarded in 1868 and 1886 respectively.

Along with his mathematical interests, Delannoy wrote about local history, painted, and from 1896 to 1915 served as the president of the Société des Sciences Naturelles et archéologiques de la Creuse.