John Knight (1740-1795) was the son of Elizabeth James, heir of Olton End, Warwickshire, and Edward Knight (1699-1780), a successful ironmaster, whose family came to prominence in the late 17th and early 18th Centuries, with furnaces at Flaxley in the Forest of Dean, Willey in Shropshire and Cookley and Whittington in the Stour valley. They formed part of the 'Ironworks in Partnership', a group which comprised of several ironmasters, a major force in the British charcoal industry of the period.
John married Henrietta Cunyngham, daughter of Daniel Cunyngham, of St. Kitts, West Indies. The family's ironworks further expanded during the 1740s and 1750s, with the purchase of Aston furnace and a forge at Bromford, near Birmingham. By the 1750s, the Knight's ironworks were responsible for around eight per cent of Britain's total pig iron output. John's elder brother, Edward Knight (1734-1812), a key figure in the family business, commissioned the building of Wolverley House, Worcestershire, in the early 1750s, and formed a notable collection of Old Master Paintings. Edward remained unmarried, and thus Wolverley passed to John's son, John Knight (1765-1850), under whom the ironworks were continued.
Wolverley House was gifted to the Sebright Educational Trust by Richard Ayshford Knight (1902-1961) in 1944. The Knight family were connected to the Sebrights by the marriage of Sir John Sebright (1725-1794) to Sarah Knight (1744-1833), sister to Edward and John. Sir John's father, William Sebright, Mayor of London in the early 17th Century, established the Educational Trust for the children of his native Wolverley. The contents of Wolverley House was sold at Christie's on 1 December 1944, including other portraits of the Knight family by Joseph Wright of Derby, and works by Sir Joshua Reynolds and Thomas Gainsborough.