Unity Mitford summered at the Berghof where she continued to discuss a possible German-British alliance with Hitler, going so far as to supply lists of potential supporters and enemies. At the 1939 Bayreuth Festival, Hitler warned Unity and her sister Diana that war with Britain was inevitable within weeks and they should return home. Diana returned to England, while Unity chose to remain in Germany, though her family sent pleas for her to come home. After Britain's declaration of war on Germany on 3 September 1939, Unity was distraught. Diana Mitford told an interviewer in 1999: "She told me that if there
The Mitfords: Letters Between Six Sisters scalding wit and best selling novelist; Pamela, who craved a quiet country life; Diana, the fascist jailed during the Second World War; Unity, whose obsession with Hitler led to her demise, Jessica, the runaway communist; and Deborah, the socialite who became Duchess of Devonshire. The book was well received both critically and commercially. In particular previously held perceptions were challenged. India Knight wrote in the "Sunday Times"; "we didn’t really know them especially well, it turns out. Jessica was not that good; Diana briefly sinister but also clever, kind, fatally loyal to her Blackshirt husband, Oswald Mosley, and so on."