Founded in 1929 by l'Union des œuvres catholiques de France (The Union of Catholic Works of France; UOCF), the weekly newspaper targeted readers aged 11 to 14 to become part of l'Action catholique des enfants (The Catholic Action for Children; ACE).

Cœurs Vaillants was a weekly newspaper, targeting readers aged 11 to 14 to become a movement of the church, l'Action catholique des enfants (The Catholic Action for Children; ACE), an organization which continues to this day.

The following year, in 1930, The Adventures of Tintin, the series of comic albums created by Belgian cartoonist Hergé, began print syndication with Cœurs Vaillants.

Cœurs Vaillants was also the first venue for the cartoonist Cabu who won a competition at age 12 and saw his first published drawing appear in the newspaper.

The French comics series Sylvain et Sylvette was created by Maurice Cuvillier in 1941 and appeared first on the pages of Cœurs Vaillants.