Geoffrey de Mandeville (d. c. 1100) was one of the great magnates of the reign of William the Conqueror. King William granted him large estates, primarily in Essex, but in 10 other shires as well. He served as sheriff in London and Middlesex, and perhaps also in Essex and in Hertfordshire. He may also have been custodian of the Tower of London.
His lands were inherited by his son William de Mandeville.
Geoffrey de Mandeville, 1st Earl of Essex (d. 1144) was famous (or infamous) for changing sides several times during the Anarchy of the reign of king Stephen. He was the son of William de Mandeville and grandson of the Geoffrey de Mandeville above.
Geoffrey de Mandeville, 2nd Earl of Essex (d. 1160) was the eldest son of the 2nd Earl above. He died without children and was succeeded by his brother William de Mandeville, 3rd Earl of Essex.
Geoffrey de Mandeville of Marshwood, Devon, was a minor landholder during the reign of Henry I, sometimes confused with the others of the same name, to whom he was not related.