Career
He represented Charlevoix in the Legislative Assembly of the Province of Canada from 1861 to 1866 and in the Legislative Assembly of Quebec from 1871 to 1875 as a Liberal member. He was born in Baie-Saint-Paul, Quebec, the son of Louis-Joseph Gagnon and Marguerite Durette,(aka Marguerite Durette dit Rochefort). Gagnon was a justice of the peace and a lieutenant in the militia for Charlevoix County.
He served as mayor of the parish of Saint-Pierre-et-Saint-Paul from 1845 to 1857 and as county warden.
Gagnon was married twice: to Ursule Garneau in 1833 and to Adelphine Huot in 1855. He was an unsuccessful candidate for a seat in the Legislative Council in 1856 and 1857.
In 1867, he ran unsuccessfully for a seat in the Canadian House of Commons. Gagnon died in the parish of Saint-Pierre-et-Saint-Paul at the age of 75.
