As described in historical dictionaries

Patronymica Britannica (1860)

BEAUVOIR. DE BEAU VOIR. Derived from a follower of the Conqueror, called Beauvois, Avho liy some genealogists is made father of the S'ir Bevis of Hamptoun, of medieval romance (which, however, represents him as a pre-Norman). The family afterwards settled in Guernsey, then in COS. Suffolk and Middlesex. The De Beavoirs of Berks, the De Beauvoirs of

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.


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