He was educated at St. John’s College, Cambridge, and began his political career as M.P. for Tiverton in 1784. His junior ministerial career began as undersecretary of state for foreign affairs, in 1789, and continued with his appointments in February 1791 as paymaster of the forces and vice president of the Board of Trade.
After he recovered, he was given the post of chancellor of the Duchy of Lancaster, which entailed no departmental responsibilities but allowed him a seat in the cabinet. He lost office again with the death of Pitt in 1806, but became president of the Board of Trade in 1809, in the ministry of Spencer Perceval.
In 1812 he was made Lord President of the Council in Lord Liverpool’s government, and he remained in this post through the end of George Canning’s government in August 1827. Harrowby resigned in November 1827, during the premiership of the Viscount Goderich (later the first Earl of Rjpon), and refused the premiership after Goderich resigned in January 1828. After that, he played a diminishing role in politics. He died on 26 December 1847.
Harrowby was a Tory and a strong supporter of William Pitt, the Younger. His close association with Pitt, and Harrowby’s distinguished record as a junior minister, led to his appointment as foreign secretary in Pitt’s government, with a place on the cabinet, in May 1804. However, Harrowby fell ill and left office in December of the same year.
In 1795 he married Lady Susan Leveson-Gower, the sixth daughter of the Marquess of Stafford.