Adelaide of Normandy

Adelaide of Normandy (or Adeliza) (c. 1030 – bef. 1090) was the sister of William the Conqueror and was Countess of Aumale in her own right.

She was a natural daughter of Robert the Magnificent, Duke of Normandy and born c.1030 Elisabeth Van Houts, in her article Les femmes dans l’histoire du duché de Normandie (or Women in the history of ducal Normandy) mentions Countess Adelaide as one of those notable Norman women who were known to have exerted a strong influence on their children especially with regard to passing on their own family history.

Adelaide's first marriage to Enguerrand II, Count of Ponthieu potentially gave then Duke William a powerful ally in upper Normandy. But at the Council of Reims in 1049, when the marriage of Duke William with Matilda of Flanders was prohibited based on consanguinity, so were those of Eustace II, Count of Boulogne and Enguerrand of Ponthieu, who was already married to Adelaide. Adelaide's marriage was apparently annulled c.1049/50 and another marriage was arranged for her, this time to Lambert II, Count of Lens, younger son of Eustace I, Count of Boulogne forming a new marital alliance between Normandy and Boulogne. Lambert was killed in 1054 at Lille, aiding Baldwin V, Count of Flanders against Emperor Henry III. Now widowed, Adelaide resided at Aumale, probably part of her dower from her first husband, Enguerrand, or part of a settlement after the capture of Guy of Ponthieu, her brother-in-law. As a dowager Adelaide began a semi-religious retirement and became involved with the church at Auchy presenting them with a number of gifts. In 1060 she was called upon again to form another marital alliance, this time to a younger man Odo, Count of Champagne. Odo seems to have been something of a disappointment as he appears on only one of the Conqueror's charters and received no land in England; his wife being a tenant-in-chief in her own right.

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