William de Mandeville (died before 1130)[1] was an Anglo-Norman baron and Constable of the Tower of London.
[2] He was Constable of the Tower of London at that time,[3] and thus keeper of the first person known to be imprisoned there for political reasons, Ranulf Flambard.
Regardless, as a punishment, in 1103 Henry I confiscated the three richest of William's Essex estates, Sawbridgeworth, Saffron Walden, and Great Waltham, comprising about a third of his entire holdings, as well as the constableship giving them to Eudo Dapifer, William’s father-in-law.
William married Margaret, daughter of Eudo FitzHubert (Dapifer)[7] and Rohese de Clare.
[6][8] William and Margaret's son Geoffrey de Mandeville would recover the seized estates and the constableship during the reign of King Stephen.