John Poyntz Spencer, 5th Earl Spencer, KG, KP, PC, known as Viscount Althorp from 1845 to 1857, was a British Liberal Party politician under, and close friend of, prime minister William Ewart Gladstone. He was twice Lord Lieutenant of Ireland.

Vice-Admiral Frederick Spencer, 4th Earl Spencer, KG, CB, PC, styled The Honourable Frederick Spencer until 1845, was a British naval commander, courtier, and Whig politician. He initially served in the Royal Navy and fought in the Napoleonic Wars and the Greek War of Independence, eventually rising to the rank of Vice-Admiral. He succeeded his elder brother as Earl Spencer in 1845 and held political office as Lord Chamberlain of the Household between 1846 and 1848 and as Lord Steward of the Household between 1854 and 1857. In 1849 he was made a Knight of the Garter.