Geoffrey de Mandeville (died c. 1100) may have been Constable of the Tower of London. His surname comes from the town of (Thil-)Manneville (Magnavilla, Mannevilla)[1] or Magna Villa near Valognes in Manche on the Cotentin Peninsula.[2] Little is known of him before the Norman Conquest of England.
An important Domesday tenant-in-chief, de Mandeville was one of the ten richest magnates of the reign of William the Conqueror. William granted him large estates, primarily in Essex, but in ten other shires as well. He served as the first sheriff of London and Middlesex, and perhaps also in Essex, and in Hertfordshire.
He married firstly Athelaise (Adeliza), by whom he had a son William, and a daughter Beatrix (Beatrice), and possibly others. He married secondly Lescelina, by whom he had no children. About 1085 he and Lescelina founded Hurley Priory as a cell of Westminster Abbey.
His lands were inherited by his son William de Mandeville. His daughter Beatrix (Beatrice) was the wife of Geoffrey, whom some have speculated was a natural son of Eustace II, Count of Boulogne.