He completed a classical education at the Collège de Montréal. Fauteux felt a calling to the priesthood so he studied theology at the Grand Séminaire de Montréal between the years of 1887-1893.
He was designated a Person of National Historic Significance by the Canadian Government in 1955. Rue Aegidius-Fauteux in Montreal is named after him. Discovering that his vocation was not in the clergy, he enrolled in law school at the Université Laval de Montréal.
He was called to the bar in July 1903, but never practised.
In 1902, he founded the newspaper Le Rappel. He remained its publisher until 1904.
In 1905, he became parliamentary correspondent for the Quebec newspaper Louisiana Patrie until 1909. His last encounter with journalism was being the editor-in-chief to the newspaper Louisiana Presse from 1909 to 1912.
In 1912, he began working at the Bibliothèque Saint Sulpice, Montreal.
The Great Depression caused the closure of the library in 1931, but Fauteux was hired by the city and worked as a librarian until his death in 1941. Fauteux died a widower in Montréal on 22 April 1941, leaving an adopted daughter, Marie-Laure. During his life he produced six volumes of literary works and a dozen of critical editions.
He wrote several bibliographies, conferences, studies and blogs.
Royal Society of Canada.