The sixth son of the builder of Longleat, Thynne’s inheritance was limited to a small estate at Cheddar and an annuity of £20 p.a. during his minority.
Shortly after his father’s death, Thynne’s widowed mother married Sir Carew Ralegh† of Downton. Thynne thereafter became a ‘fastest friend’ of Carew’s brother, Sir Walter†. He pleaded for Sir Walter’s release from the Tower in November 1605, and was to be at Sir Walter’s side on the evening of his execution.
By September 1624 Thynne had entered the circle of the former royal favourite Robert Carr, earl of Somerset, at which time he was ‘troubled with an indisposition in his ears’. In April 1625 he sought re-election to Parliament, but Sir John Holles*, 1st earl of Clare, on whose patronage he now relied, proved unable to help, as several other notables ‘engross all’ in those boroughs ‘where my provision lay’.
Thynne was the subject of a complaint to the House of Lords in June 1641. An aggrieved clerk named William Hobson protested that he was unable to prosecute Thynne regarding possession of a house at Chelsea because Thynne had been granted parliamentary protection by the earl of Somerset. However, both Somerset and Thynne denied placing any such impediment in Hobson’s way.
