Lady Mary Agatha Russell (1853 – 23 April 1933) was the daughter of the 1st Earl Russell and Frances, Countess Russell, and the aunt of Bertrand Russell. She was the co-editor of her mother's posthumously published memoirs, Lady John Russell: A Memoir with Selections from Her Diaries and Correspondence.Lady John Russell: A Memoir with Selections from her Diaries and Correspondence. Methuen & Co, London, 1910.
