The sitter was the daughter of Admiral Sir Peter Warren, at one time M.P. for Westminster. On 7 July 1768 she married Willoughby Bertie, 4th Earl of Abingdon (1740-1799), who had succeeded to the earldom on his father's death in 1760. Described as 'one of the most steady and intrepid assertors of liberty in this age', Lord Abingdon was a close friend of the Marquis of Rockingham. A man of strong political beliefs, he attacked Burke in a popular pamphlet for the policy that led to the American War of Independence, and opposed the war with France. A full-length portrait of him by Gainsborough was sold by Major Hugh Rose in these Rooms, 1 June 1956, lot 47. Lord and Lady Abingdon had three sons and a daughter, the eldest son, Montagu (1780-1854), succeeding his father as 5th Earl.
A three-quarter-length copy of this portrait was sold in these Rooms, 6 April 1973, lot 122.