Henrietta Butler, Viscountess Galmoye, previously Henrietta Waldegrave, Baroness Waldegrave, was an illegitimate daughter of James Stuart, Duke of York, subsequently King of England, Scotland and Ireland, by his mistress, Arabella Churchill. Upon marrying, she became Lady Waldegrave, and then with her second marriage Viscountess Galmoye, as well as Countess of Newcastle.