He entered the military school of St-Cyr and took part in the war of 1870, earning the rank of Chevalier of the Legion of Honour. Sub-chief of the general staff in the years preceding the First World War, at the outbreak of the conflict he was a member of the superior council of the army and commanded the Second Army on the Lorraine front. In 1916 he took part in the defence of Verdun as chief of staff. Elected deputy at the end of the war, in 1920 he presided over the French delegation that went to Rome for the canonization of St Joan of Arc.
A fervent Catholic, after the 1924 elections—when parties unfavourably disposed toward the Catholic Church gained victory—he worked tirelessly to defend the faith and became a champion of uniting Catholic forces into a single movement. Thus arose the F.N.C. (Fédération nationale catholique), of which he was president and to which he devoted his energies until his death.