Arthur James Balfour, 1st Earl of Balfour, KG, OM, PC, DL (pronunciation: /ˈbælfʊər/ bal-foor; 25 July 1848 – 19 March 1930) was a British Conservative politician and statesman. He served as the Prime Minister of the United Kingdom from July 1902 to December 1905, and was later Foreign Secretary in 1916–1919.
Born in Scotland and educated as a philosopher, Balfour first entered parliament in the 1874 general election. At first seen as something of a dilettante, he attained prominence as Chief Secretary for Ireland from 1887–1891. In this post, he authored the Perpetual Crimes Act (1887) (or Coercion Act) aimed at the prevention of boycotting, intimidation and unlawful assembly in Ireland during the Irish Land War.
Balfour succeeded his uncle Lord Salisbury as Prime Minister and Conservative Party leader in July 1902 (Balfour had been Conservative leader in the House of Commons since 1891). As Prime Minister, Balfour oversaw such events as the Entente Cordiale, but his party was split over tariff reform and in December 1905 he relinquished power to the Liberals. The general election the following January was a disaster for the Conservatives and their Liberal Unionist allies, left with a mere 157 seats in Parliament. Balfour himself lost his Manchester East seat and was rushed back to parliament in a by-election for the City of London constituency. He continued as Leader of the Opposition throughout the crisis over the Lloyd George People's Budget and the Parliament Act, but after failing to win either of the two General Elections in 1910 he resigned as leader in November 1911.
He returned to the Cabinet as First Lord of the Admiralty in the coalition government formed in May 1915, then in David Lloyd George's coalition government he was Foreign Secretary (1916–1919). In this post, he authored the Balfour Declaration of 1917, supporting the establishment of a Jewish homeland in Palestine, and for which his name perhaps remains best known today. Balfour retired from the House of Commons at the 1922 general election, and was granted an Earldom. In the late 1920s he served as an elder statesman in the second government of Stanley Baldwin.