Sir William Jerningham, 6th Baronet, de jure 7th Baron Stafford (7 March 1736 – 14 August 1809) was an English landowner.

[1] His maternal grandparents were Francis Plowden, an MP for Bannow who served as Comptroller of the Household of the exiled Jacobite court of James II, and Mary Stafford-Howard (eldest daughter of Hon.

[1] Jerningham was the representative of one of the few remaining families of English Gentry prior to the Conquest, and was descended on many sides from King Edward III.

[5] Together they were the parents of:[1] Sir William died at his seat, Costessey Hall in Norfolk, on 14 August 1809.

[8] His youngest son Edward designed the St. Augustine Chapel at the family seat which opened the week after his death in 1809.