Lord Iveagh (often popularly known as Benjamin Iveagh) was born into the Anglo-Irish Guinness family, being the son of Arthur Onslow Edward Guinness, Viscount Elveden, and Lady Elizabeth Cecilia Hare, daughter of the Richard Hare, 4th Earl of Listowel. His father, Viscount Elveden, was a Major in the 55th (Suffolk and Norfolk Yeomanry) Anti-Tank Regiment of the Royal Artillery and was killed in action by a V-2 rocket while serving in Belgium on 8 February 1945. In 1947, his mother remarried Edward Rory More O'Ferrall.