When the senior male-line ended in the mid-12th century, the two branches descended from their heiress adopted the Warenne surname.

[5] Orderic Vitalis describes William as Roger's consanguineus, literally "cousin" but more generically a term of close kinship that is not typically used to describe brothers, and Roger de Mortemer appears to have been a generation older than William de Warenne.

These occurrences have historically been interpreted as representing a single Radulf with successive wives, with Beatrice being the mother of William and hence identical to Gunnor's unnamed niece.

[5] A reevaluation of the evidence led Katherine Keats-Rohan to suggest that the traditional view has mistakenly compressed two distant men of the same name into a single chimeric individual.

Associations with the village of Vascœuil led Keats-Rohan to identify the latter with a 1054/60 widow, Beatrice, daughter of Tesselin, vicomte of Rouen, and since another Rouen vicomte married a niece of Gunnor, this may represent the connection to the ducal family to which Robert de Torigny alluded.

[28] The family held the Earldom of Surrey for three generations, before William de Warenne, 3rd Earl of Surrey, died on crusade in 1148, leaving an only daughter and heiress, who married successively William of Blois, the son of King Stephen, and Hamelin, illegitimate half-brother of king Henry II.

Similar arms were also adopted by his brother in law, the famous Crusader Ralph I de Beaugency who had married an older sister, Matilda.

[29] Among the holdings of William de Warenne, 1st Earl of Surrey was some land in Whitchurch, Shropshire, and this likely led to his kin becoming its early lords.

[31] However, in a later publication Charles Travis Clay elaborated on Farrer's original work and drew attention to a Domesday tenant of William de Warenne, 1st Earl of Surrey, named Ranulf nepos (nephew).

[37] Reginald de Warenne, younger brother of the 3rd Earl, married the heiress of Wormegay, Norfolk.