William was the second son of Giroie, Lord of Échauffour and Gisle, daughter of Thurston de Bastembourg lord of Montfort-sur-Risle.
The regiment saw further service in Northern France, including helping in the capture of Lisieux on 23 August, and later crossing the Risle, advancing rapidly to the Seine.
He was decorated with the Military Cross by King George VI for engineering a bridge in an advance action at the Risle River near Brionne, France.
A baroque castle, Château du Champ-de-Bataille lies between the communes of Neubourg and Sainte-Opportune-du-Bosc, and in the Campagne du Neubourg, between the river Risle to the west and the river Iton to the east.
He was also feudal lord of Pont-Audemer, a settlement built around the first bridge to cross the River Risle upstream of its estuary, shared with the River Seine.