Wulmar was a 7th-century French priest and Benedictine abbot born in the County of Boulogne. After being forcibly separated from his wife, Osterhilda, due to a prior betrothal agreement, he dedicated his life to religious service. He initially served as a lay brother at Hautmont Abbey, performing manual labor such as tending cattle. Following his ordination to the priesthood, he lived as a hermit in the forest near Mount Cassel before eventually establishing monastic communities near Samer.