Maud, Abbess of Montivilliers was a natural daughter of Henry I of England by an unknown mistress. She is not to be confused with Isabel, another illegitimate daughter of Henry I by his mistress Isabel de Beaumont (c. 1102 – c. 1172), herself a sister of Robert de Beaumont, 2nd Earl of Leicester.
Maud (or Mathilda) was a half-sister of the Empress Matilda, who agreed to work with her. She may have valued her company and advice.
Matilda became the abbess of the Abbey Church of Notre-Dame, Montivilliers, and for that reason is best known as Maud of Montivilliers.