Earl of Radnor is a title which has been created twice. It was first created in the Peerage of England in 1679 for John Robartes, 2nd Baron Robartes, a notable political figure of the reign of Charles II. He was made Viscount Bodmin at the same time. Robartes was the son of Richard Robartes, who had been created Baronet in July 1621 and Baron Robartes, of Truro, in the Peerage of England in 1626. All three titles became extinct on the death of the fourth Earl in 1757. Anna Maria Hunt, great-niece of the fourth Earl, married the Hon. Charles Bagenal-Agar, youngest son of James Agar, 1st Viscount Clifden of Gowran. Their son Thomas James Agar-Robartes was created Baron Robartes in 1869. For more information on this title, see the Viscount Clifden.
The earldom was created for a second time in the Peerage of Great Britain in 1765 when William Bouverie, 2nd Viscount Folkestone, was made Earl of Radnor. The Bouverie family descends from William des Bouverie, a prominent London merchant. He was created a baronet, of St Catherine Cree Church, London, in the Baronetage of Great Britain in 1714. His eldest son, the second Baronet, represented Shaftesbury in the House of Commons. He was succeeded by his younger brother, the third Baronet. He sat as Member of Parliament for Salisbury until he was raised to the Peerage of Great Britain as Baron Longford and Viscount Folkestone in 1747.
His son, the second Viscount, also represented Salisbury in Parliament. In 1765 he was made Baron Pleydell-Bouverie, of Coleshill in the County of Berkshire, and Earl of Radnor. The earldom was created with remainder, failing heirs male of his body, to the heirs male of his father. Both peerages were in the Peerage of Great Britain. He was succeeded by his son, the second Earl. He was Member of Parliament for Salisbury and served as Lord Lieutenant of Berkshire. The second Earl assumed the additional surname of Pleydell after succeeding to the estates of his maternal grandfather, Sir Mark Stuart Pleydell, 1st Baronet (see Pleydell Baronets). His son, the third Earl, represented Downton and Salisbury in the House of Commons. On his death the titles passed to his son, the fourth Earl. He served as Lord Lieutenant of Wiltshire.
He was succeeded by his son, the fifth Earl. He sat as Conservative Member of Parliament for South Wiltshire and Enfield and held political office as Treasurer of the Household from 1885 to 1886 under Lord Salisbury. His son, the sixth Earl, represented Wilton (also known as South Wiltshire) in Parliament as a Conservative and served as Lord Lieutenant of Wiltshire. He was succeeded by his son, the seventh Earl. He notably held the honorary posts of Keeper of the Privy Seal and Lord Warden of the Stannaries and was made a Knight of the Garter in 1962. As of 2009 the titles are held by his grandson, also William Pleydell-Bouverie, the 9th Earl of Radnor, who succeeded his father in 2008.
Successive Earls of Radnor were governors of the French Hospital from the eighteenth century to 2015.
The family seat are Longford Castle, near Salisbury, Wiltshire, and Alward House, near Alderbury, Wiltshire.
Richard Robartes, 1st Baron Robartes (d. 1634)
John Robartes, 2nd Baron Robartes (1606–1685) (created Earl of Radnor in 1679)
John Robartes, 1st Earl of Radnor (1606–1685)
Robert Robartes, Viscount Bodmin (1634–1682)
Charles Bodvile Robartes, 2nd Earl of Radnor (1660–1723)
Henry Robartes, 3rd Earl of Radnor (1695–1741)
John Robartes, 4th Earl of Radnor (1686–1757)
Sir William des Bouverie, 1st Baronet (1656–1717)
Sir Edward des Bouverie, 2nd Baronet (c. 1690–1736)
Sir Jacob des Bouverie, 3rd Baronet (1694–1761) (created Viscount Folkestone in 1747)
Jacob des Bouverie, 1st Viscount Folkestone (1694–1761)
William Bouverie, 2nd Viscount Folkestone (1725–1776) (created Earl of Radnor in 1765)
William Bouverie, 1st Earl of Radnor (1725–1776)
Jacob Pleydell-Bouverie, 2nd Earl of Radnor (1750–1828)
William Pleydell-Bouverie, 3rd Earl of Radnor (1779–1869)
Jacob Pleydell-Bouverie, 4th Earl of Radnor (1815–1889)
William Pleydell-Bouverie, 5th Earl of Radnor (1841–1900)
Jacob Pleydell-Bouverie, 6th Earl of Radnor (1868–1930)
William Pleydell-Bouverie, 7th Earl of Radnor (1895–1968)
Jacob Pleydell-Bouverie, 8th Earl of Radnor (1927–2008)
William Pleydell-Bouverie, 9th Earl of Radnor (born 1955)
The heir apparent is the present holder's eldest son Jacob Pleydell-Bouverie, Viscount Folkestone (born 1999)
In the course of an episode of the Dutch television show Verborgen Verleden, which is similar to the British Who Do You Think You Are?, the Dutch architect Jan des Bouvrie found that his family was descended from Jehan de le Bouvrie (born about 1480), of Sainghin-en-Mélantois, where his widow, Jeanne de la Motte, inherited a farm with four cows and two horses in 1543. A grandson of Jehan, the merchant Lawrence de Bouverie, born in Sainghin, migrated to England, where his descendant William des Bouverie, became the ancestor of the Earls of Radnor. Jan des Bouvrie hoped to meet the present-day Lord Radnor, but was unsuccessful, as Radnor would not agree to meet him.