This progenitor of one of the noblest and most powerful families on either side of the channel is simply alluded to by Wace as "li Sire de Magnevile" (l. 13,562).
The French antiquaries, whilst agreeing as to the individual present at Hastings, differ respecting the locality whence he derived his name; Mons. Le Prévost considering it to be Magneville, near Valonges, while Mons. Delisle reports that it was Mandeville le Trévières, the Norman estates of the Magnavilles, Mandevilles, or Mannevilles, as they were indifferently called, lying partly in the neighbourhood of Creulli, and the rest round Argentan, where, at a later period, they held the honour of Chamboi.
No particular feat of arms is attributed to him by the Norman poet. He is only mentioned as one who rendered great aid in the decisive battle, and we find him in consequence rewarded with ample domains in England at the time of the great survey, amounting to one hundred and eighteen lordships in various counties, of which Walden, in Essex, was the chief seat of his descendants, who became the first Norman earls of that county in the reign of Stephen.
He was also the first Constable of the Tower of London after the Conquest, an office enjoyed by his grandson of the same name, which I mention on account of the interesting fact that, in the charter of the Empress Matilda, which confers this amongst many other honours bestowed upon him, the custody of the Tower of London is granted to him and his heirs, with the little castle there (described, in another charter as under it) which belonged to Ravenger.
This charter in which she creates Geoffrey de Mandeville (grandson of the companion of the Conqueror) Earl of Essex, is stated in a marginal note in Dugdale's Baronage to be "the most ancient creation charter which hath been ever known," and, I may add, for the numberless concessions and privileges recorded in it, the most remarkable.
To return to the first Geoffrey, we learn from his charter of foundation of the Benedictine Monastery of Hurley, in Berkshire, that he was twice married. His first wife Athelaise (Adeliza) being the mother of his heir William de Mandeville, and other children not named; and his second wife, Leceline, by whom he appears to have had no issue.
Mr. Stapleton, in his annotations to the Norman Rolls of the Exchequer, suggests that Adeliza, the first wife of Geoffrey, was sister to Anna, wife of Turstain Haldub, mother of Eudo al Chapel.
Added to this site through the courtesy of Fred L. Curry, who provided a photocopy of the section.