Thomas Prowse was a parliamentarian and an amateur architect. He was the son of John Prowse (1676-1710) of Compton Bishop near Axbridge and Berkley, M.P. for Somerset, and Abigail Hooper, daughter of George Hooper, Bishop of Bath and Wells. On 1 March 1731 he married Elizabeth, the daughter of John Sharp of Grafton Park, Northamptonshire, by whom he had three sons and five daughters.
Prowse was returned unopposed at five elections for one of the Somerset seats. He spoke frequently in the House and in October 1761 Prowse was considered a suitable candidate for Speaker but he declined as he had 'a fear of impairing [his] health'. He was offered other positions but declined these too and rarely attended the House during the 1760s.
Prowse was clearly a much-admired man. The inscription on the sitter's monument in Axbridge church gives him fulsome praise: 'He discharged his duty in Parliament with ability, integrity and honour...ever attentive to promote the Interest and Happiness of others than his own...'.
The portrait of Thomas Prowse follows the pose of the three-quarter- length portrait of Prowse by William Hoare at Berkley near Frome, and Gainsborough may have been forced to use another portrait of the sitter who 'on account of a distemper [was unable] to sit long in a chair at a time' (Letter from the Duke of Newcastle to the Duke of Bedford dated 20 October 1761 quoted by Namier & Brook, 1985, p.335).
Two further versions of each of these pictures exist. A portrait of Mrs Thomas Prowse was bought by the Leeds City Art Gallery in 1946 and is on loan to Temple Newsam House.