The Cliveden Set were a 1930s, upper class group of prominent individuals politically influential in pre-World War II Britain, who were in the circle of Nancy Astor, Viscountess Astor. The name comes from Cliveden, the stately home in Buckinghamshire, which was then 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 this Germanophile social network was in favour of friendly relations with Germany. John L. Spivak, writing in 1939, devotes a chapter to the Set. Norman Rose's 2000 account of the group proposes that, when gathered at Cliveden, it functioned more like a think-tank than a cabal. Ironically, according to Carroll Quigley, the Cliveden Set had been strongly anti-German before and during World War I.
The actual beliefs and influence of the Cliveden Set are matters of some dispute, and in the late 20th century some historians of the period came to consider the Cliveden Set allegations to be exaggerated. For instance, Christopher Sykes, in a sympathetic 1972 biography of Nancy Astor, argues that the entire story about the Cliveden Set was an ideologically motivated fabrication by Claud Cockburn that came to be generally accepted by a public looking for scapegoats for British pre-war appeasement of Adolf Hitler. There are also academic arguments that while Cockburn's account may have not have been entirely accurate, his main allegations cannot be easily dismissed.