The Cliveden Set were a 1930s upper-class group of prominent people, who were politically influential before the Second World War in the United Kingdom. They were in the circle of Nancy Astor, Viscountess Astor, the first female Member of Parliament to take her seat. The name comes from Cliveden, a stately home in Buckinghamshire that was Astor's country residence.
The "Cliveden Set" tag was coined by Claud Cockburn in his journalism for the communist newspaper The Week. It has long been widely accepted that the aristocratic Germanophile social network was for friendly relations with Nazi Germany and helped create the policy of appeasement. John L. Spivak, writing in 1939, devoted a chapter to the Cliveden Set. Norman Rose's 2000 account of the group proposes that when it gathered at Cliveden, it functioned more like a think-tank than a cabal. According to Carroll Quigley, the Cliveden Set had been strongly anti-German before and during World War I.
After the Second World War ended, the discovery of the Nazis' Black Book showed that all the group's members were to be arrested as soon as Britain had been invaded. Lady Astor remarked, "It is the complete answer to the terrible lie that the so-called 'Cliveden Set' was pro-Fascist".
The actual beliefs and influence of the Cliveden Set are matters of some dispute. In the late 20th century, some historians of the period came to consider the allegations about it to have been exaggerated. For instance, Christopher Sykes, in a sympathetic 1972 biography of Nancy Astor, argued that the entire story about the Cliveden Set had been an ideologically-motivated fabrication by Cockburn that came to be generally accepted by a public, which was looking for scapegoats for the British prewar appeasement of Adolf Hitler. Some academic arguments have stated that Cockburn's account may have not have been entirely accurate, but his main allegations cannot be easily dismissed.