William Beresford, 1st Baron Decies

On 16 June 1763, Beresford married Elizabeth FitzGibbon (1732–1807), daughter of John FitzGibbon and wife Isabella Grove. Elizabeth's brother was John FitzGibbon, 1st Earl of Clare, the Lord Chancellor of Ireland. They had nine children, four sons and five daughters:^[3]

• Brig-Gen. Marcus Beresford (1764–1803), who died unmarried.^[1]
• Rev. John Beresford, 2nd Baron Decies (1773–1855), who married Charlotte Philadelphia Horsley, only daughter and heiress of Robert Horsley.^[4]
• Hon. Rev. George Beresford (1776–1842), who married Susannah Gorges in 1798.^[1]
• Hon. Rev. William Beresford (1780–1830), who married Lady Anna Bennet, daughter of the 4th Earl of Tankerville, in 1804.^[1]
• Hon. Catherine Eleanor Beresford (d. 1837), who married Rev. William Armstrong in 1789.^[1]
• Hon. Araminta Anne Beresford (d. 1816), who married the Very Rev. Arthur John Preston in 1794.^[1]
• Hon. Harriet Beresford (d. 1834), who married Thomas Henry Bermingham Daly Sewell in 1796.^[1]
• Hon. Frances Beresford (d. 1864), who married Col. Thomas Burrowes in 1797.^[1]
• Hon. Louisa de la Poer Beresford (d. 1851), who married Thomas Hope in 1806. After his death in 1831, she married her first cousin William Beresford, 1st Viscount Beresford in 1832.^[1]

Lord Decies died in September 1819, aged 76, and was succeeded in the barony by his eldest surviving son John;^[1] his eldest son Marcus had died in 1803.^[3]

Through his third son, he was a grandfather of British Army officer Marcus Beresford (1800–1876), who was also an MP for Northallerton and Berwick-upon-Tweed.^[5]

Through his youngest daughter Louisa, he was a grandfather of British MP and patron of the arts, Henry Thomas Hope (1808–1862), whose daughter Henrietta married Henry Pelham-Clinton, 6th Duke of Newcastle, and British MP Alexander Beresford Hope (1820–1887), who married Lady Mildred Gascoyne-Cecil (a daughter of James Gascoyne-Cecil, 2nd Marquess of Salisbury).^[1]

• Kidd, Charles; Williamson, David (eds.). Debrett's Peerage and Baronetage (1990 ed.). New York: St Martin's Press.
• Leigh Rayment's Peerage Pages ^{[self-published source] [better source needed]}
• "William Beresford, 1st Baron Decies". Thepeerage.com.
• Venn, J. A., ed. (1940). Alumni Cantabrigienses. London: Cambridge University Press.