Research Notes:
Keats-Rohan states, [1]
William de Albini Brito was a younger son of the Breton seigneur Main of Saint-Aubin-d'Aubigné (Ille -et-Vailaine) and his Norman wife Adelaide de Bohun. His cognomen Brito distiquished him from his Norman namesake, the Pincerna, who came from Saint-Martin-d'Aubigny (Manche). He assisted in the vitory of Tinchebray in 1106, and became high in favour with henry I, attesting numerous royal charters, the earliest belonging to the period 1104 to 1116. He married Cecilia, daughter of Roger Bigod and Adeliz de Tosny and (after her mother's death post 1136) principal coheiress of her maternal grandfather Robert de Tosny, lord of the honour of Belvoir in Lincolnshire (d. 1088) (Sanders, 12). William appears to have held land in Lincolnshire, Leicestershire, Essex, Hertfordshire and Northamptonshire, some or all of which washis wife's marriage portion. The bulk of the Tosny inheritance, however, including Belvoir, appears not ot have been held by William and Cecilia until c. 1130, after the death of Cecilia's mother Adeliz. Cecilia's younger sister Maud married William de Albini Pincerna. In 1130 William appears as an itinerant justice in Lincolnshire. Between 1135 and 1143 he attested a number of Lincolnshire charters by King Stephen. In 1146 Stephen granted William's estates to Ranulf of Chester. The general tenor of the grant, and the absence of any indication that WIlliam had joined the Empress, indicate that Stephen was granting the overlordship of William's estates in order to gain Ranulf's support, and not that William had suffered any royal disfavour. William was alive at least until 1148, the earliest possible date fo for a charter he gave for Pipewell abbey (Northants.) By his wife (who survived him) he had issue two daughters, Matilda and Basilia, and four or five sons, including his eventual successor in Belvoir William II (d. 1168) and Ralph, who died at the siege of Acre in 1191. Much of the information on William's family comes from the Liber Vitae of Thorney Abbey (BL ADD. 40,000, fol. 2r), where their anniversaries were remembered. William and Cecilia completed the foundation of Belvoir priory, begun by Robert de Tosny. They and many of their descendants were buried there.
[1] K. S. B. Keats-Rohan, Domesday Descendants, A Prosopography of persons occurring in English documents, 1066-1166: II Pipe Rolls to Cartae Baronum (Boydell Press, 2002), 271.