Margaret de Newburg, 7th Countess of Warwick (died 3 June 1253) was the daughter of Henry de Beaumont, 5th Earl of Warwick

Henry de Beaumont, 5th Earl of Warwick

Henry de Beaumont, 5th Earl of Warwick , Earl of Warwick, Baron of Hocknorton and Hedenton, was the son of Waleran de Beaumont, 4th Earl of Warwick and Margaret, daughter of Henry de Bohun, 1st Earl of Hereford and Maud of Essex...

 and Margaret D'Oili. She was sister and heiress of Thomas de Beaumont, 6th Earl of Warwick

Thomas de Beaumont, 6th Earl of Warwick

Thomas de Beaumont, 6th Earl of Warwick , Earl of Warwick, Baron of Hocknorton and Hedenton, was the son of Henry de Beaumont, 5th Earl of Warwick and Margaret D'Oili...

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She married first John Marshal, and secondly John du Plessis. The latter was a great favourite of Henry III

Henry III of England

Henry III was the son and successor of John as King of England, reigning for 56 years from 1216 until his death. His contemporaries knew him as Henry of Winchester. He was the first child king in England since the reign of Æthelred the Unready...

, who in 1247 created him the seventh Earl of Warwick

Earl of Warwick

Earl of Warwick is a title that has been created four times in British history and is one of the most prestigious titles in the peerages of the British Isles.-1088 creation:...

 and subsequently Count of Warwick. He died 20 February 1263. There was no issue by either of these marriages and so at Margaret's death the estates passed to her cousin, William Maudit

William Maudit, 8th Earl of Warwick

William Maudit , 8th Earl of Warwick was an English nobleman and participant in the Barons' War....

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