Emma Fitz-Osborn or Emma de Breteuil, and later Emma de Guader, was a Norman noblewoman, the wife of Ralph de Guader and the daughter of William FitzOsbern, Lord of Breteuil and later first Earl of Hereford of a new creation, who was a cousin and close adviser of William the Conqueror. William's opposition to their marriage led to the unsuccessful Revolt of the Earls.

Ralph de Gaël was the Earl of East Anglia and Lord of Gaël and Montfort. He was the leading figure in the Revolt of the Earls, the last serious revolt against William the Conqueror.