An old presentation plaque on frame reads 'Lady Delamere by Mrs Beale', inscribed on reverse of canvas 'Mary wife to Henry, Earl of Warrington'. Circa 1670.

Mary Langham (1652-1691) was the only child to survive from the several marriages of Sir James Langham, second baronet, of Cottesbrooke, Northamptonshire. She married Henry Booth (1652-1694), politician and the eldest surviving son of George Booth, second baronet and first Baron Delamer in July 1670 at St Helen's in Bishopsgate in London, a reflection of the long standing Langham business interests and political ties in the city.  Their first born son died as an infant and the surviving children included three other sons, George Booth, later the second Earl, Langham and Henry and two daughters, Elizabeth and Mary. Henry was created Earl of Warrington in 1690.

Mary Beale (born Craddock in March 1633) was a prolific English portrait painter, becoming one of the most important portrait painters of the middle classes in 17th century England and has been described as the first professional female English painter.  She was born in Barrow, Suffolk where her father was a rector and married Charles Beale in 1651. She possibly studied under Robert Walker but later was chiefly influenced by Lely who was a friend and whose work he sometimes allowed her to make copies of. Her most active period was in the 1670's and 80's. Her husband's and kept very detailed notes of her studio activities and the notebooks for 1677 and 1681 survive, found at the Bodleian Library, Oxford and The National Portrait Gallery, London, respectively and Vertue published partial transcripts of others. Her style was often characterised by the feigned stone oval cartouche with fruit as in this portrait and her work often displays her talent in depicting her subjects with particular sensitivity and charm such as in her portraits of her two young sons, Bartholomew and Charles, found in Tate Britain, London and in her own self portrait found in the National Portrait Gallery, London.  She died in Pall Mall and was buried in St James's London in October 1699.