(image: Robert Harley, 1st Earl of Harley and Mortimer; source: Wikimedia Commons)
The impeachment and trial of Robert Harley, Earl of Oxford and Tory Cabinet Leader from 1710 to 1714, is a classical episode of British parliamentary and political history. Harley supported peace with France, and withdrew British troops from the front in May 1712. The Franco-British preliminaries of peace (October 1711) set out the blueprint of the later peace treaties of Utrecht (11 April 1713) and Rastatt (6 March 1714). Holy Roman Emperor Charles VI and the Dutch Republic felt betrayed by this decision. When Queen Anne died in August 1714, Hanoverian Elector Georg Ludwig von Braunschweig-Lüneburg, her closest Protestant relative, succeeded her. Shortly after his arrival in Britain, the new sovereign appointed a Whig-dominated Cabinet. Subsequently, the new majority, led by James Viscount Stanhope and the Earl of Sunderland, persecuted the previous political masters, accusing them of treason. Whereas Lord Bolingbroke (Secretary of State for the Southern Department) managed to escape to France, Lord Harley was sentenced and imprisoned in the Tower. This internal settlement of accounts, however, did not deter the new Whig-administration from pursuing a foreign policy akin to that of their predecessors.
Robin Eagles (History of Parliament Trust) discusses this well-documented case in a recent podcast (video, above or audio, here).