William Jefferson Hague, Baron Hague of Richmond, (born 26 March 1961) is a British Conservative Party politician and life peer who served as Leader of the Conservative Party and Leader of the Opposition from 1997 to 2001. He was the Member of Parliament (MP) for Richmond (Yorks) in North Yorkshire from 1989 to 2015. He served in the Cameron government as First Secretary of State from 2010 to 2015, Foreign Secretary from 2010 to 2014, and Leader of the House of Commons from 2014 to 2015.

Hague was educated at Wath Comprehensive School, the University of Oxford and INSEAD, subsequently being elected to the House of Commons at a by-election in 1989. Hague quickly rose through the ranks of the government of John Major and was appointed to Cabinet in 1995 as Secretary of State for Wales. Following the Conservatives' defeat at the 1997 general election by the Labour Party, he was elected Leader of the Conservative Party at the age of 36.

Hague resigned as Conservative leader after the 2001 general election following his party's second defeat, at which the Conservatives made a net gain of just one seat. He returned to the backbenches, pursuing a career as an author, writing biographies of William Pitt the Younger and William Wilberforce. He also held several directorships, and worked as a consultant and public speaker.

After David Cameron was elected Leader of the Conservative Party in 2005, Hague was reappointed to the Shadow Cabinet as Shadow Foreign Secretary. He also assumed the role of Senior Member of the Shadow Cabinet, serving as Cameron's deputy. Following the formation of the coalition government in 2010, Hague was appointed First Secretary of State and Foreign Secretary. Cameron described him as his "de facto political deputy". On 14 July 2014, Hague stood down as Foreign Secretary and became Leader of the House of Commons. He did not stand for re-election at the 2015 general election and was succeeded by Rishi Sunak. He was awarded a life peerage in the 2015 Dissolution Honours List on 9 October 2015.