Ignace De Coussemaker joined the Comité Flamand de France in 1862. Later on he became its vice-president, together with François Van Costenoble. He belonged to Guido Gezelle’s Northern French circle of friends. He was an alderman in Bailleul, had a distinct interest in history and fully supported the regionalist movement. He published a number of studies, e.g. about 16th century Bailleul. He was a member of the Commission historique du Nord (The North French History Committee) and the Société d’émulation de Bruges (History Society of Bruges). With the help of Gezelle he was appointed honorary foreign member of the Royal Flemish Academy of Linguistics and Literature. Gezelle wrote his in memoriam in the Academy’s Yearbook. The remnants of his personal library still exist and are kept in the abbey of Zevenkerken near Bruges.