William Stourton, 18th Baron Stourton

He is chiefly remembered for the private memoirs of his relative Maria Fitzherbert, the secret wife of King George IV, which she dictated to him, and which formed the basis for her first biography, published by his brother Charles Langdale in 1856.

Mary Langdale and Maria Fitzherbert were first cousins through their shared grandparents, Sir John Smythe, III Baronet of Acton Burnell, and his wife Constantia Blount who were themselves twelfth cousins, twice removed, by way of their shared ancestors, of Edward I of England and his second wife Margaret of France; William and Maria were also related by marriage, as mentioned above, William's wife, Catherine Winifred Weld was a niece of Mrs Fitzherbert's first husband, Edward Weld; also, William's sister, the Hon.

He was a witness on the celebrated occasion, 24 August 1833, when she permitted the Duke of Wellington to burn a horde of her private papers relating to her secret marriage to George IV.

[4] At her special request, a number of documents that she particularly valued, including her marriage certificate, were preserved and deposited in Coutts Bank, sealed and witnessed by Stourton.

Soon after Mrs. Fitzherbert's death, Stourton took great offence at the publication of the Memoirs of Lord Holland, which claimed that she had never regarded herself as more than a royal mistress.

Charles was unable to obtain the documents deposited in Coutts Bank, but he used his brother's memoir as the basis for his biography of Mrs. Fitzherbert, published in 1856.