Earldom of Radnor

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.

...
Wikipedia