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In page Alianore Holland, Countess of March:

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Alianore Holland, Countess of March (also spelt Eleanor;[citation needed] 13 October 1370 – October 1405) was the eldest daughter of Thomas Holland, 2nd Earl of Kent, and the wife of Roger Mortimer, 4th Earl of March, heir presumptive to her uncle, King Richard II. Through her daughter, Anne Mortimer, she was the great-grandmother of the Yorkist kings Edward IV and Richard III. She was governess to Richard II's wife, Isabella of Valois.