|Bishop of Exeter|
|Diocese||Diocese of Exeter|
|Other post(s)||Dean of Windsor (1765–1777)|
|Born||19 January 1728|
|Died||27 December 1777(aged 49)|
|Parents||Willem van Keppel, 2nd Earl of Albemarle|
Lady Anne Lennox
|Spouse||Laura Walpole (married 1758)|
|Alma mater||Christ Church, Oxford|
Keppel was the fifth and fourth surviving son of Willem van Keppel, 2nd Earl of Albemarle and his wife Lady Anne Lennox, daughter of Charles Lennox, 1st Duke of Richmond, illegitimate son of King Charles II. His older brothers were George Keppel, 3rd Earl of Albemarle, who had succeeded their father as earl, Augustus Keppel, 1st Viscount Keppel, an admiral, raised to the peerage in his own right and the politician and military commander Hon. William Keppel.
After his graduation, Keppel was appointed Canon of the Eleventh Stall at St George's Chapel, Windsor in 1754, acting as chaplain first to King George II of Great Britain and then to the latter's son King George III of the United Kingdom. He was consecrated as Bishop of Exeter in 1762 and became Dean of Windsor as well as consequently Register of the Order of the Garter three years later, holding all three posts until his death in 1777.
On 13 September 1758, he married Laura Walpole, sister of Maria, Duchess of Gloucester and Edinburgh and eldest daughter of the Hon Edward Walpole, a son of Robert Walpole, 1st Earl of Orford. They had four children, three daughters and one son:
- Anna Maria (d. 1836), who married Lt.-Gen. William Stapleton. They had one son, Lt.-Col. John Horace Stapleton.
- Frederick (12 Nov 1762-12 Apr 1830), who married Louisa Clive, daughter George Clive MP. They had three sons.
- Laura (14 Mar 1765-29 Jun 1798), who married George FitzRoy, 2nd Baron Southampton. They had two daughters, of which one, Georgiana, married her cousin Lt.-Col. John Stapleton.
- Charlotte Augusta (1771-1852), who married Robert Foote, Gentleman of the King's Privy Chamber and High Sheriff of Kent. They had no known issue.
- Debrett, John (1828). Debrett's Peerage of the United Kingdom of Great Britain and Ireland. Vol. I (17th ed.). London: G. Woodfall. p. 136.
- Burke, John (1832). A Genealogical and Heraldic History of the Peerage and Baronetage of the British Empire. Vol. I (4th ed.). London: Henry Colburn and Richard Bentley. p. 22.
- Collins, Arthur (1812). Sir Egerton Brydges (ed.). Collin's Peerage of England. Vol. I. London: T. Bensley. pp. 740–741.
- Haydn, Joseph (1851). The Book of Dignities: Containing Rolls of the Official Personages of the British Empire. London: Longman, Brown, Green and Longman's. pp. 351.
- "ThePeerage - Rt. Rev. Hon. Frederick Keppel". Retrieved 25 December 2006.
- Oliver, George (1861). Lives of the Bishops of Exeter and a History of the Cathedral. Exeter: William Roberts. pp. 163–164.