The son of Thomas, First Baron Pelham of Laughton and Lady Grace Holles. He was the younger brother of Thomas Pelham, the Duke of Newcastle. He was educated at Christ Church, Oxford. Through family connections, he was quickly identified by Robert Walpole as a rising star. His first post was as a Lord of the Treasury at the tender age of 25. He would then serve as secretary for war and paymaster of the forces. In 1743 a coalition saw the two brothers serving side by side - although not always showing eye to eye agreement on everything. As Prime Minister, Henry did not fully prosecute the War of Austrian Succession and quietly pulled away from the conflict.