During the First World War, he served with the 16th Chasseurs à cheval Regiment stationed at Beaune, and was decorated with the Croix de Guerre with a silver star.
The latter convinced Canard to return to the Maghreb, first as a teacher in the Lycée de Tunis and then as a professor in the Faculty of Letters of the University of Algiers.
It was there that Canard, along with Georges Marçais, founded the Institut d'Études Orientales and began a journal that soon acquired international prominence among Orientalists: the Annales.
Among Canard's major scholarly achievements are his history of the Hamdanid dynasty, as well as his studies on the Fatimid Caliphate, a field which at the time was otherwise the almost exclusive reserve of Vladimir Alexeyevich Ivanov (1886–1970).
He also made important contributions on the history of Muslim relations with the Byzantine Empire, and along with the Belgian Henri Grégoire (1881–1964) supervised the French edition of Alexander Vasiliev's (1867–1953) monumental Byzantium and the Arabs (Византия и арабы).