Henri Lagrange (born 21 November 1893 in Paris; died 30 October 1915 in Montereau-Fault-Yonne) was a journalist and monarchist activist in France.

A Camelot du roi, he became famous for allegedly insulting President Armand Fallières or shouting "Down with the Republic!

[2] This act resulted in a six-month prison sentence, served under common law, despite efforts on his behalf by over 150 writers and artists, including Guillaume Apollinaire, Frédéric Mistral, and Francis Jammes.

Maurice Barrès dedicated pages to him in Familles spirituelles de la France (1917), describing him as a "storm bird" and "torrent stone, full of sparks."

Georges Bernanos also referenced him in his novel Under the Sun of Satan (1926), stating, "The new generation was clearly marked by his sacrifice."