Prowse’s five elections for Somerset were all unopposed. He soon made his mark in the House, and Horace Walpole in 1766 described him as ‘the most knowing and the most moderate of the Tories’.
When on Pitt’s resignation in October 1761 George Grenville, Speaker designate, became leader of the House, Prowse proved the most popular candidate for the Chair. Newcastle at first thought that ‘a Tory will not go down’, but found from letters received from his ‘principal Whig friends (not courtiers) in the country ... that Mr. Prowse will go down very well with them, and indeed better than anybody. This ... shows how unanimously and honourably Mr. Prowse will be chose.’ Nomination to the Chair was therefore offered to him by Grenville, but was refused, not from ‘a fear of impairing my health, but being already in such a condition as would make it impossible for me to go through the common and necessary business of the House for one month’ (‘on account of a distemper’, wrote Newcastle to Bedford, 20 Oct., ‘which does not permit him to sit long in a chair at a time’.)
With regard to the peace preliminaries Newcastle, in his list of 13 Nov. 1762, classed Prowse as ‘doubtful’; when the House met, 25 Nov., H. B. Legge, a friend of Prowse, described him as ‘in suspense what to do’;
It would seem by my last accounts from England that some people must have begun to recover their senses, for I see parties balancing. It is a strange infatuation that for the sake of punishing one impudent worthless fellow, persons that have a grain of understanding or honesty left should be desirous of throwing down all the fences of their liberties, which the wisdom and courage of their ancestors had provided.
And Robert Nugent to Grenville, from Bath, 20 Oct. 1764:
Prowse is here, not at all well, and lives very much retired. I have heard some things of him which I do not entirely like, although they are only symptomatic.
Rockingham, writing to Newcastle, 3 Jan. 1765, about the need ‘to meet frequently and concert plans of operation’, included Prowse among those whom it would be most desirable to have at such meetings; and in June, considering his future Government, described him as ‘a very proper man to be got’. Prowse was offered the office of cofferer but declined. In September 1766 Chatham offered him the Post Office, and he again declined; and in Rockingham’s list, compiled in November 1766, was marked as ‘absent’.
Prowse ‘was a country gentleman with a practical interest in architecture’.
