Background
Mildmay was a younger son of Benjamin Mildmay, 17th Baron FitzWalter, by the Honourable Catherine, daughter of William Fairfax, 3rd Viscount Fairfax of Emley.
Mildmay was a younger son of Benjamin Mildmay, 17th Baron FitzWalter, by the Honourable Catherine, daughter of William Fairfax, 3rd Viscount Fairfax of Emley.
He served as First Lord of Trade between 1735 and 1737 and as Treasurer of the Household between 1737 and 1755. Mildmay served as Commissioner of Excise between 1720 and 1728. In 1730 he created Viscount Harwich, in the County of Essex, and Earl FitzWalter.
In 1735 he was sworn of the Privy Council and appointed First Lord of Trade under Sir Robert Walpole, a post he held until 1737, and then served as Treasurer of the Household between 1736 and 1755.
He was also Lord-Lieutenant of Essex from 1741 to 1756.