William d'Aubigny (Brito)

William d'Aubigny (d. after 1148), was an itinerant justice under King Henry I of England. He was commonly known by the appellation Brito.

William was a son of Main d'Aubigny, Breton lord of Saint-Aubin-d'Aubigné (now in Ille-et-Vilaine department) and Adelaide de Bohun. He fought at the Battle of Tinchebray (1106) and was high in Henry I's favor. He was allowed to marry Cecily, the elder daughter of Roger Bigod, sheriff of Norfolk. Through her, he acquired a part of the honour of Belvoir in Leicestershire - his castle became the centre of the family estates - after his mother-in-law, who had been the heir of Robert de Tosny, lord of Belvoir, died about 1130. The couple had four or five sons and two daughters. His heir was William, who married Maud Fitz Robert, daughter of Robert Fitz Richard. The Magna Carta surety, William d'Aubigny, was their son.