The youngest son of Thomas Pelham, he was educated at Corpus Christi College, Cambridge, and became a fellow of Peterhouse in 1751.
[1] In the same year, he was returned for Bramber as a Government supporter;[2] the electoral patronage there was leased by Lord Archer from Sir Henry Gough, who controlled it.
[4] Pelham apparently took little interest in politics, and in 1758, through the patronage of his second cousin once removed, the Duke of Newcastle, obtained an appointment as a Commissioner of Customs.
Pelham's political detachment led him to be spared in December 1762, when other relatives of Newcastle were removed from office.
[5] They had three children: Pelham succeeded his brother John in the Catsfield and Crowhurst estates in 1786.