He was one of the best scholars of his day, and attained to the headship of his old school and college: he served as Headmaster of Westminster 1753–1765, and Dean of Christ Church 1767–1776. Between those headships, he held the deanery of Rochester 1765–1767. He held from time to time a number of livings, and in 1771 was made Bishop of Chester and tutor to the Prince of Wales (later George IV). In 1776 he became Archbishop of York, and also Lord High Almoner and privy councillor.