The son of Frederick Ponsonby, third Earl of Bessborough; he was educated at Harrow and was a Whig MP for Poole (1826-31), Knaresborough (1832), and Dorset (1832-27). He was raised to the peerage in 1838.

REFERENCES TO William Francis Spencer Ponsonby, first baron de Mauley:

Lady Caroline Lamb to Lady Morgan, 27 May 1823 in Lady Morgan’s Memoirs: Autobiography, Diaries and Correspondence. Second Edition, Revised 2 vols (London: Wm. H. Allen & Co., 1863)

Lady Caroline Lamb to William Godwin, [1824?] in William Godwin: his Friends and Contemporaries (London: Henry S. King & Co., 1876)

Lady Caroline Lamb to Lady Morgan, [June 1825?] in Lady Morgan’s Memoirs: Autobiography, Diaries and Correspondence. Second Edition, Revised 2 vols (London: Wm. H. Allen & Co., 1863)

Lady Caroline Lamb to Lady Morgan, [June 1825?] in Lady Morgan’s Memoirs: Autobiography, Diaries and Correspondence. Second Edition, Revised 2 vols (London: Wm. H. Allen & Co., 1863)

Lady Caroline Lamb to Lady Morgan, [October 1825?] in Lady Morgan’s Memoirs: Autobiography, Diaries and Correspondence. Second Edition, Revised 2 vols (London: Wm. H. Allen & Co., 1863)