Research Notes:

Loyd indicates that this family originated in Saint-Hilaire-du-Harcouët in the present-day French département of Manche, arrondissement Mortain, canton Saint-Hilaire-du-Harcouët.

["Apud oppidum Santi Hilarii, Harchodio vicecomite, Petro fratre eius" witnessed the undated charter under which "Radulfus Filogerensis et uxor eius Avicia" donated revenue to Sainte-Trinité de Fougères. It appears likely that "Harchodio vicecomite" was the same person as Asculf de Saint-Hilaire but this is not beyond doubt.] "…Hasculfo de Sancto Jacobo…" witnessed the charter dated to [1100/01] under which Henry I King of England confirmed donations by "Hugo de Grentemesnil" to Saint-Evroul. “…Hasculfo de Sancto Hylario…" witnessed the charter dated to [1100/04] under which Guillaume Comte de Mortain confirmed donations to Saint-Martin de Marmoutier. ¹