DERWENTWATER, EARL OF, an English title borne by the family of Rauclyffe or Radcliffe from 1688 to 1716, when the 3rd earl was attainted and beheaded, and claimed by his descendants, adherents of the exiled house of Stuart, from that date until the death of the last male heir in 1814. Sir Francis Radclyffe, 3rd baronet (1625-1697), was the lineal descendant of Sir Nicholas Radclyffe, who acquired the extensive Derwentwater estates in 1417 through his marriage with the heiress of John de Derwentwater, and of Sir Francis Radclyffe, who was made a baronet in 1619. In 1688 Sir Francis was created Viscount Rad clyffe and earl of Derwentwater by James II., and dying in 1697 was succeeded as 2nd earl by his eldest son Edward who had married Lady Mary Tudor (d. 1726), a natural daughter of Charles II. The 2nd earl died in 1705, and was succeeded by his eldest son James (1689-1716), who was born in London on June 28, 1689, and was brought up at the court of the Stuarts in France as companion to Prince James Edward, the old Pretender. In 1710 he came to reside on his English estates. Joining the Stuart rising of 1715, Derwentwater escaped arrest owing to the devotion of his tenantry, and in October, with about 7o followers, he joined Thomas Forster at Green-rig. When the rebels capitulated at Preston he was conveyed to London and impeached. Pleading guilty at his trial he was attainted, and was beheaded on Tower hill on Feb. 24, 1716, declaring on the scaffold his devotion to the Roman Catholic religion and to King James III.
On the death of the 3rd earl's son, John Radclyffe, in 1731 his uncle Charles (1693-1746), son of the 2nd earl, took the title of earl of Derwentwater. Charles Radclyffe had fought at Preston and was condemned to death for high treason; but, more fortunate than James, he escaped from prison and went to live in Rome. He was captured by an English ship in Nov. 1745 whilst proceeding to join Charles Edward, the young Pretender, in Scotland. He was beheaded on Dec. 8, 1746. His eldest son, James Bartholomew (17 2 5-1786 ), who had shared his father's imprisonment, then claimed the title of earl of Derwentwater, and on his mother's death in 1755 became 3rd earl of Newburgh. His only son and successor, Anthony James (1757-1814), died without issue in 1814, when the title became extinct de facto as well as de jure. The present representative of the Radclyffe family is Lord Petre, and in 1874 the bodies of the first three earls of Derwentwater were reburied in the family vault of the Petres at Thorndon, Essex.
See R. Patten, History of the Late Rebellion (London, 1717) ; W. S. Gibson, Dilston Hall, or Memoirs of James Radcliffe, earl of Derwent water (London, 1848-185o) ; G. E. C(okayne), Complete Peerage (Exeter, 1887-1898) ; and Dictionary of National Biography, vol. xlvii. (London, 1896) .