Dictionary of National Biography, 1885-1900/Cowper, Mary
COWPER, MARY, first Countess Cowper (1685–1724), daughter of John Clavering of Chopwell, Durham, was married to William, first earl Cowper [q. v.], in 1706. The marriage was kept secret for some months (September 1706 to February 1707). The first letter which she wrote to her husband after the marriage bears the following endorsement by him: ‘First letter received from my wife, formerly Mrs. Clavering, having been privately married to her without consummation, by which it appears I judged rightly of her understanding; I hope also of her other good qualities; I was not induced to the choice by any ungovernable desire; but I very coolly and deliberately thought her the fittest wife to entertain me and to live as I might when reduced to a private condition, with which a person of great estate would hardly have been contented,’ &c. She seems to have been a lady of considerable attractions, intelligence, and accomplishments. On the accession of George I she was appointed a lady of the bedchamber to the Princess of Wales, with whom she had corresponded for some years, and whose confidante she became. Though of a Jacobite family, she ardently espoused her husband's political principles. On entering the royal household she began to keep a diary, an imperfect copy of which was lent in manuscript to Lord Campbell, and freely used by him for the purpose of his biography of Lord Cowper. It was edited, with the addition of a subsequently discovered fragment, from the original manuscript, with an introduction, notes, and appendices, by the Hon. Spencer Cowper in 1864 (London, 8vo). It consists of two fragments, the first covering the period between October 1714 and October 1716, the second being the record of little more than two months, April and May 1720, during which the negotiations for the reconciliation of the king and Prince of Wales were in progress. The records of the intermediate and subsequent periods were destroyed by Lady Cowper in 1722, when her husband fell under suspicion of complicity in the Jacobite plot, and she was apprehensive lest his house might be searched. The earlier papers probably contained matter relating to the quarrel between the king and the prince which would not have been grateful to the former. The reason for destroying the later papers is not apparent, as it seems very unlikely that Cowper was really involved in the conspiracy. Lady Cowper survived her husband by about four months, dying on 5 Feb. 1723–4.
[Diary of Mary, Countess Cowper, 1714–20, edited by the Hon. Spencer Cowper, London, 1864, 8vo, 2nd edition, 1865; Hist. Reg. Chron. Diary, 1724, p. 10.]