Arthur James Balfour, 1st Earl of Balfour, KG, OM, PC, DL 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 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. 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 of 1911, but after failing to win either of the two General Elections in 1910 he resigned as leader in November 1911.