William Murray, 1st Earl of Mansfield, PC (2 March 1705 – 20 March 1793), was a British judge, politician, lawyer, and peer best known for his reforms to English law. Born in Scone Palace, Perthshire, to a family of Scottish nobility, he was educated in Perth before moving to London at the age of 13 to study at Westminster School. Accepted into Christ Church, Oxford, in May 1723, Mansfield graduated four years later and returned to London, where he was called to the Bar by Lincoln's Inn in November 1730 and quickly gained a reputation as an excellent barrister.
He became involved in British politics in 1742, beginning with his election to the House of Commons as a Member of Parliament for Boroughbridge and appointment as Solicitor General. In the absence of a strong Attorney General, Mansfield became the main spokesman for the government in the House of Commons, where he was noted for his "great powers of eloquence" and was described as "beyond comparison the best speaker". With the promotion of Sir Dudley Ryder to Lord Chief Justice in 1754, Mansfield became Attorney General and, when Ryder unexpectedly died several months later, he took his place as Chief Justice.