The anthologies of letters between the sisters should come with those decoder rings that used to be hidden inside cereal boxes. As the eldest child (a lone brother Tom was killed in action in 1945), Nancy’s teasing humor shaped the vocabulary that’s come to be recognized as “Mitfordian.” She is said to have invented most of the elaborate, extensive nicknames for the family and their large group of famous friends. The Mitfords are usually written about as a pack, though it’s Nancy who is most responsible for the enduring Mitford mythology, thanks not only to the success of the semi-autobiographical account of their eccentric childhood in The Pursuit of Love, but also to her letters, which she left behind in the thousands. ( The Wikipedia entry for that phrase is a lengthy chart detailing who among the group is lightly fictionalized as whom in the books they all wrote about one another.) Little wonder that the family dynamics dominated newspaper headlines for decades starting in the 1920s, when Nancy and Diana were debutantes, prominent among the cast of Bright Young Things. Jessica, the Communist, and then the journalist. Then there was Diana, known first as a great beauty of her generation, then as the fascist. Pamela, the “boring” one, as Tina Brown described in a New York Times review of a 2016 group biography.

Just now, a Mitford revival has been sparked by the excellent adaptation of the eldest sister’s popular postwar novel The Pursuit of Love. Their associations and affairs are the stuff of 20th-century-history exams. And why not? They were beautiful, aristocratic, and wild. Still, every now and then, there is a flurry of new, or renewed, interest in the Mitford girls. After close to a century of tabloid features on one or all six of them, the youngest and last surviving died in 2014 at age 94. The Mitford sisters never really go anywhere-they are all dead, so perhaps a difficult task.

Hons and Rebels by Jessica Mitford