A younger son of Sir John Pelham, 3rd Baronet, he was returned for two Parliamentary constituencies in Sussex, where the family held considerable influence, for most of the time between 1690 and 1702.
[2] Henry was classed by Lord Carmarthen as a Whig, but his Parliamentary activity at the time is not easily distinguished from that of his brother Thomas, who sat for Lewes.
Trevor's judicial appointment in June allowed Henry to again take up the Lewes seat at the November 1701 English general election, having meanwhile loaned the town £200.
[3] Unlike Thomas, Henry was held to be a reliable Whig, and in January 1702, he acted as teller against hearing the Maidstone election case before the bar of the House.
[1] The death of Sir John Pelham in January 1703 gave rise to an extended falling-out between Thomas and Henry over the division of their father's estate.