[1] In 1047, the local baron, Grimoult du Plessis, was executed for an attempted coup against William the Bastard (later William the Conqueror), the Duke of Normandy, and his lands were given to the duke's half brother, Odo, the Bishop of Bayeux, to become part of his diocese.

The church building and priory in its current location were built in the late 13th century under the direction of Prior Guillaume Causson, Henri I's successor.

The time his new position required him to spend at court meant he could no longer serve as Bishop of Condom.

To compensate his son's tutor, Louis XIV appointed him to be the prior of Le Plessis-Grimoult.

During his time as prior, he had a dispute with Julian de Saint-Germain, the priest of Maisoncelles-la-Jourdan, over the collection of tithes.

[5] The priory served the parishes of Le Plessis-Grimoult, Roullours, Carville, Chênedollé, Truttemer-le-Grand, Montsecret, Sainte-Honorine-la-Chardonne, Saint-Jean-le-Blanc, Campandré, Montchauvet, Frênes, Saint-Vigor-des-Mézerets, Périgny, Cauville, Proussy, Bernières-le-Patry, Maisoncelles-la-Jourdan, Estry, Saint-Christophe-de-Chaulieu, Beauchêne, Clairefougère, Saint-Cornier-des-Landes, Saint-Jean-des-Bois, Saint-Quentin-les-Chardonnets, Yvrandes, Bonnemaison, Courvaudon, Feuguerolles-Bully, Fontaine-Étoupefour, Rosel, La Cambe, Osmanville, Mondrainville, Noyers-Bocage, Planquery, Saint-Germain-d'Elle, Bretteville-le-Rabet, Campeaux and Colombelles.