Lady Margaret Boleyn[2] (c. 1454 – 1539) was an Irish noblewoman, the daughter and co-heiress of Thomas Butler, 7th Earl of Ormond.
She had two sisters: Anne who married Sir James de St Leger, by whom she had issue, and Elizabeth.
Anne and Margaret claimed to be co-heiresses of their father and the Earldom of Ormond, but their cousin, Piers Butler, who had physical control of the Irish estates and the backing of the Irish Council, claimed to be the heir through the direct male line.
Her son, the ambitious courtier Thomas Boleyn, became the first Earl of Wiltshire and by his marriage to Elizabeth Howard, the daughter of the Earl of Surrey, the future Duke of Norfolk, he was the father to Anne Boleyn, Queen Consort of England.
[6] From around 1519 onward, she was declared by inquisition to have suffered periods of insanity making her incapable of managing her own estates.