William Capell, 3rd Earl of Essex

William Capell, 3rd Earl of Essex, KG PC (11 January 1697 – 8 January 1743) was an English courtier and diplomat.

He was the son of the 2nd Earl of Essex.

Capell was one of the founding governors of the charity, the Foundling Hospital, created in October 1739 to care for abandoned children.

On 27 November 1718, Capell married Lady Jane Hyde, a daughter of the 4th Earl of Clarendon and they had two children:

Lady Jane died in 1724 and William married Lady Elizabeth Russell, a daughter of the 2nd Duke of Bedford on 3 February 1726 and they had one living son, William Anne Capell, 4th Earl of Essex (1732–1799) who married Frances Hanbury Williams.

"". Dictionary of National Biography. London: Smith, Elder & Co. 1885–1900.