This is a oil on canvas portrait of John Montresor (1736-1799), a British military engineer. It was screen-captured in sections and stitched together, and has, as a result, been slightly cropped.
American Colonial Era Painter, 1738-1815
John Singleton Copley (1738[1] - 1815) was an American painter, born presumably in Boston, Massachusetts and a son of Richard and Mary Singleton Copley, both Irish. He is famous for his portrait paintings of important figures in colonial New England, depicting in particular middle-class subjects. His paintings were innovative in their tendency to depict artifacts relating to these individuals' lives. china oil painting John Singleton Copley a British military engineer