(b London, 1698; bur. Kensington, Middlesex [now in London], 28 Dec. 1778).
English portrait painter, a pupil of Richardson. He was in Italy 1725–32 and in 1736 he became a foundation member of and official painter to the Society of Dilettanti, a social club for gentlemen who had visited that country. His 23 portraits of his fellow members (1741–9, several still in the possession of the Society) are considered his finest works. Most of them show the members in fancy dress. These portraits are in oil, but otherwise Knapton worked mainly in pastel. He had a great reputation as a connoisseur and from 1765 until his death he was Surveyor of the King's Pictures. By the time of his appointment he seems to have given up painting. Cotes was his most important pupil.