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Artware Fineart has dated this piece to the 18th Century.
Signed/Inscribed:
incorrectly inscribed on the old canvas (now relined) " Rt Hon Diana /Baroness Barham" (the only daughter of Lady Middleton )

oil on canvas
28 x 24in. (71.12 x 60.96 cm.)
Provenance : Ryman Gallery
Margaret Middleton formerly Gambier Born about 1740 Daughter of James Gambier and Mary (Mead) Gambier, Sister of Susan (Gambier) Cornish, James Gambier and John Gambier . She married Admiral Charles Middleton, 1st Baron Barham, son of Robert Middleton and Helen Dundas, on 21 December 1761 at St. Martin-in-the-Fields Church, Covent Garden, London, England . Middleton, RN who was then a Post Captain and commanding HMS Emerald. He met Margaret through Captain Mead who was her Uncle, who he had encountered aboard HMS Sandwich some twenty years earlier. Margaret moved to Teston in Kent, to be close to her friend Elizabeth Bouverie. In 1763, after service aboard the Adventure Charles Middleton moved to join Margaret at Teston, and for the next twelve years they farmed the land belonging to Mrs Bouverie. Margaret was mother of Diana (Middleton) Noel. She died on 10 October 1792 at Teston, Kent, England. Margaret was not only an accomplished artist she was also very well connected in society. She was considered one of the most “accomplished women of her time,” she used her connections and considerable influence to push for the first bills for abolition in British Parliament (qtd. in Rendell 45).

In 1784, her husband Sir Charles Middleton was elected Tory Member of Parliament (MP) for Rochester, a seat he held for six years, and on 24 September 1787 he was promoted rear admiral. By 1786 he had become disillusioned with his role as Comptroller of the Navy, seeing it as beset by internal politics between the Admiralty and the Navy Board. In 1786 he prepared a letter to the First Lord of the Admiralty indicating he would "contend no more for the public," and urging the appointment of a successor who could "have more weight than I have had, and influence ministers to correct these evils."The letter was never sent, but Middleton resigned his position in 1790 and effectively retired from naval affairs.

Promotions based on seniority continued to be received, despite Middleton's retirement from active service. On 1 February 1793 he was promoted to vice admiral, and in May 1794 he was appointed to the Board of Admiralty. He became First Naval Lord in March 1795 and was promoted to full admiral on 1 June 1795. He was finally, in May 1805 (at the age of 80), appointed First Lord of the Admiralty. He was also created Baron Barham, of Barham Court and Teston in the County of Kent, with a special remainder, failing male issue, to his only child, his daughter, Diana Noel, 2nd Baroness Barham, and her male heirs.

Margaret and her husband Charles Middleton played a crucial role in the abolition of the slave trade in the British Empire. They had been influenced by a pamphlet written by Rev. James Ramsay, who served as a surgeon under Middleton aboard HMS Arundel in the West Indies, but later took holy orders and served on the Caribbean island of St Christopher (now St Kitts), where he observed first-hand the treatment of slaves. On his return in 1777, exhausted by the continuing conflict with influential planters and businessmen, Ramsay returned to Britain and briefly lived with Sir Charles and Lady Middleton at Teston. He later became vicar of Teston and rector of Nettlestead, Kent, the livings being in the gift of Middleton. Lady Middleton (1730-1792): As the daughter of an upper-class British family, her parents expected her to marry a suitor of their choosing. But Margaret defied her parents and married the man of her choice, even though it meant losing her fortune.
Ramsay's pamphlet Essay on the Treatment and Conversion of African Slaves in the British Suga
Artware Fineart has dated this piece to the 18th Century.
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