Robert Harley, 1st Earl of Oxford and Earl Mortimer, KG PC FRS was an English statesman and peer of the late Stuart and early Georgian periods. He began his career as a Whig, before defecting to a new Tory ministry. He was raised to the peerage of Great Britain as an earl in 1711. Between 1711 and 1714 he served as Lord High Treasurer, effectively Queen Anne's chief minister. He has been called a prime minister, although it is generally accepted that the de facto first minister to be a prime minister was Robert Walpole in 1721.

The Tories were a loosely organised political faction and later a political party, in the Parliaments of England, Scotland, Ireland, Great Britain and the United Kingdom. They first emerged during the 1679 Exclusion Crisis, when they opposed Whig efforts to exclude James, Duke of York from the succession on the grounds of his Catholicism. Despite their fervent opposition to state-sponsored Catholicism, Tories opposed his exclusion because of their belief that inheritance based on birth was the foundation of a stable society.