Robert Anthony Eden, 1st Earl of Avon, (12 June 1897 – 14 January 1977) was a British politician who served as Prime Minister of the United Kingdom and Leader of the Conservative Party from 1955 until his resignation in 1957.
Achieving rapid promotion as a young Conservative member of Parliament, he became foreign secretary aged 38, before resigning in protest at Neville Chamberlain's appeasement policy towards Mussolini's Fascist regime in Italy. He again held that position for most of the Second World War, and a third time in the early 1950s. Having been deputy to Winston Churchill for almost 15 years, Eden succeeded him as the leader of the Conservative Party and prime minister in 1955, and a month later won a general election.
Eden's reputation as a skilled diplomat was overshadowed in 1956 when the United States refused to support the Anglo-French military response to the Suez Crisis, which critics across party lines regarded as a historic setback for British foreign policy, signalling the end of British influence in the Middle East. Most historians argue that he made a series of blunders, especially not realising the depth of American opposition to military action. Two months after ordering an end to the Suez operation, he resigned as Prime Minister on grounds of ill health, and because he was widely suspected of having misled the House of Commons over the degree of collusion with France and Israel.
Eden is generally considered to be among the least successful of British prime ministers in the 20th century, although two broadly sympathetic biographies have gone some way to shifting the balance of opinion. He was the first out of fifteen British prime ministers to be appointed by Queen Elizabeth II in her seventy-year reign.
Eden was born on 12 June 1897 at Windlestone Hall, County Durham, into a conservative family of landed gentry. He was the third of four sons of Sir William Eden, 7th and 5th Baronet, and Sybil Frances Grey, a member of the prominent Grey family of Northumberland.