Walpole’s aim in Memoirs of the Reign of King George III was not to chronicle events year by year (October 1760 – February 1772), as he had done in Memoirs of King George II, but to defend what he called his ‘return to action’ and to attack those who had thwarted it. Yet previous editors, first Sir Denis le Marchant in 1845 and then G. F. Russell Barker in 1894, abridged or altered much of what Walpole said about his friends and his enemies, and left out most of his lies and fantasies about the British Royal Family. These editors produced a narrative that seemed impersonal as well as impartial, the work of a detached spectator rather than a committed participant. The present edition is the first to go back to the manuscripts and give Walpole’s text in its entirety, unabridged and unexpurgated, together with an introduction and annotation designed to help reassess the value of the memoirs as historical evidence.