Daughter and heir of Robert D'Arcy, fourth earl of Holdernesse; in 1773 she married Francis Osborne, marquess of Carmarthen, who divorced her following her affair with Captain John Byron whom she married in 1779. She was the mother of Augusta Byron, the poet's half-sister.

REFERENCES TO Amelia Byron, baroness Darcy (de Knayth) [née Darcy]:

Lord Byron to Thomas Moore, 27 September 1813 in Letters and Journals of Lord Byron 2 Vols (London: John Murray, 1830)

Lord Byron to John Murray, 10 December 1821 in Letters and Journals of Lord Byron 2 Vols (London: John Murray, 1830)