Politician. The son of James Balfour, who died in his mid-thirties and younger brother of Prime Minister Arthur Balfour (1848 - 1930) and embryologist Francis Balfour (1851-82). Balfour was educated at Eton and Trinity College (Cambridge). He was elected Member of Parliament for Leeds in 1885, serving until 1906. He acted as Private Secretary to his brother (1885-6), was Chief Secretary for Ireland (1895 - 1900) and President of Board of Trade (1900-5). He succeeded his brother to the Earldom of Balfour in 1930.