Her later years were bittersweet, as the success of her biographical studies of Madame de Pompadour, Voltaire and King Louis XIV contrasted with the ultimate failure of her relationship with Palewski.

The few months she spent there represented almost the whole of her formal schooling; in the autumn the family moved to a larger house in Victoria Road, Kensington, after which Nancy was educated at home by successive governesses.

At the end of the war Redesdale decided to sell Batsford Park and move his increasing family (a fifth daughter, Jessica, had been born in September 1917) to less extravagant accommodation.

[34] Although there was undoubtedly cruelty in her taunting—the other children, led by Tom, formed a "Leag (sic) against Nancy"[35]—her teasing was also, according to the later reflections of her nephew Alexander Mosley: "a highly-honed weapon to keep a lot of highly competitive, bright, energetic sisters in order.

That was followed in June 1923 by her presentation at Court, a formal introduction to King George V at Buckingham Palace, after which she was officially "out" and could attend the balls and parties that constituted the London Season.

While the new house at Swinbrook was made ready, the female members of the family were sent for three months to Paris, a period which, says Hastings, began Nancy's "lifelong love affair" with France.

[61] Other biographers describe him as irresponsible, unfaithful, a bore and unable to hold down a regular job,[26] and as the model for Waugh's unscrupulous, amoral character Basil Seal from Black Mischief.

[64] When the novel was published in 1935, its book cover illustrated by Bip Pares,[65] it made little critical impact and seriously offended members of her own family, particularly her sisters Diana and Unity, both of whom were supporters of Mosley's movement and devotees of the German dictator Adolf Hitler.

[73] Early in 1939, Rodd left for southern France to work with the relief organisations assisting the thousands of Spanish refugees who had fled from General Franco's armies in the final stages of the civil war.

[76] Having rejected the political extremes within her family, Nancy Mitford was a moderate socialist,[77] but some of her works, such as her introductions to the Stanley letter collections, and her "U–non-U" essay of 1955, are staunch defences of the aristocratic traditions and values that she grew up with.

[81] Nancy, in full antifascist mode, had described her sister to the British Intelligence agency MI5 as "a ruthless and shrewd egotist, a devoted fascist and admirer of Hitler [who] sincerely desires the downfall of England and democracy in general".

Ostensibly, that was to establish a French branch of Heywood Hill, but in reality, she wished to be close to Palewski, who was now a member of de Gaulle's postwar provisional government.

[98][n 11] Mitford's visit to France in late 1945 had revived her longing to be there, and in April 1946, having given up working in the shop the previous month, she left London to make her permanent home in Paris and never lived in England again.

[104][105] In 1950 she translated and adapted André Roussin's play La petite hutte ('The Little Hut'), in preparation for its successful West End début in August,[106] The Times's critic noted the "habit of speech at once colloquial and unexpected which instantly declares itself the creation of Miss Mitford.

[108] The busy period in her writing life continued in 1951 with her third postwar novel, The Blessing, another semi-autobiographical romance this time set in Paris, in which an aristocratic young Englishwoman is married to a libidinous French marquis.

[111] The historian AJP Taylor likened Mitford's evocation of 18th-century Versailles to "Alconleigh", the fictitious country house that formed the background to her recent best-selling novels, a comparison that she found offensive.

The book also included an abbreviated version of Ross's original article,[n 12] and contributions from Waugh,[119] Betjeman, Peter Fleming and Christopher Sykes,[120] It was a tremendous success; as Lovell records, "'U and Non-U' was the buzz phrase of the day ... Nancy's comments made her the arbiter of good manners for several generations".

Mitford mainly concealed her true feelings on this separation, although one acquaintance noted her increasingly "savage" teasing of friends, which was perhaps a safety valve: "If she would only tell one she is unhappy one would do what one could to comfort her".

After the cremation, she informed her sister Jessica, "the ashes were done up in the sort of parcel he used to bring back from London, rich thick brown paper & incredibly neat knots".

The problem was resolved after a visit to the ophthalmic surgeon Patrick Trevor-Roper, who gave her new spectacles: "It is heavenly to be able to read for a long time on end & now I see how handicapped I was when doing Voltaire".

[142] "For months, Nancy had sat giggling helplessly before the drawing-room fire, her curiously triangular green eyes flashing with amusement while her thin pen flew along the lines of a child's exercise book.

[52] She may have inherited some of her natural wit and sharpness of expression from her maternal grandfather Thomas Bowles, who in his youth during the Franco-Prussian War had provided dispatches which Acton describes as "extremely graphic and amusing".

[51] Mitford was later embarrassed by her prewar novels; Rachel Cooke, writing on their reissue in 2011, believes she had no reason to be: "There is a special kind of energy here, and its engine is the admirable and irresistible commitment of a writer who would rather die than be boring".

[147] In Acton's view it and its companion volume Love in a Cold Climate present an entirely authentic picture of country house life in England between the wars, and will long be consulted by historians of the period.

[148] In these later novels Zoë Heller of the Daily Telegraph hears in the prose, behind a new level of care and artfulness, "the unmistakeable Mitford trill, in whose light, bright cadences an entire hard-to-shock and easy-to-bore view of life is made manifest".

[149] At times a more serious undertone, contrasting with the "bright, brittle, essentially ephemeral" nature of her early works,[150] becomes evident; Olivia Laing in the Guardian, discerns "a faint and beguiling pessimism about love's pursuit and its consequences" beneath the light superficiality.

[152] More recently, Philip Hensher and others have argued that although the novel is immensely enjoyable and that Mitford's "marvellous voice" is undiminished, she is on less sure ground with her "Frenchness" than with the English country house ambience, and her picture of France as the embodiment of everything civilised is less than convincing.

"[155] Similar questions were raised in the Times Literary Supplement's review, in relation to Mitford's fictional output as a whole: "Would she have been a better novelist if she had 'tried harder', gone in further, dropped the pose of amateurishness, cut the charm, looked beyond the worlds that she knew and, more importantly, loved?

In the first of these, Madame de Pompadour, she followed Waugh's advice not to write for experts but to fashion "a popular life like Strachey's Queen Victoria", with "plenty of period prettiness".

Mitford's informal style was remarked on by the literary critic Cyril Connolly, who wrote that her facility for transforming unpromising source material into readable form was a skill that any professional historian might envy.