Born at Asthall Manor, Mitford, the sixth of seven children, was the daughter of David Freeman-Mitford, 2nd Baron Redesdale, and his wife Sydney (daughter of politician and publisher Thomas Bowles), and grew up in a series of her father's country houses. She had little formal education, but nevertheless was widely read. Though her sisters Unity and Diana were well-known British supporters of Hitler and her father was described as being "one of nature's fascists", Jessica (always known as Decca) renounced her privileged background at an early age and became an adherent of communism. She was known as the "red sheep" of the family.
At the age of 19, Mitford met her second cousin, Esmond Romilly, who was recuperating from dysentery caught during a stint with the International Brigades defending Madrid during the Spanish Civil War. Romilly was a nephew (by marriage) of Winston Churchill. The cousins immediately fell in love and decided to elope to Spain, where Romilly picked up work as a reporter for the News Chronicle. After some legal difficulties caused by their relatives' opposition, they married. They moved to London and lived in the East End, then mostly a poor industrial area. Mitford gave birth at home to a daughter, Julia Decca Romilly, on 20 December 1937. The baby died in a measles epidemic the following May. Jessica Mitford rarely spoke of Julia in later life and she is not referred to by name in Mitford's 1960 autobiography, Hons and Rebels.
In 1939, Romilly and Mitford emigrated to the United States. They travelled around, working odd jobs, perpetually short of money. At the outset of World War II, Romilly enlisted in the Royal Canadian Air Force; Mitford was living in Washington D.C., and considered joining him once he was posted to England. While living in D.C, with contemporaries Virginia Foster Durr and Clifford Durr, she gave birth to another daughter, Constancia Romilly ("the Donk" or "Dinky") on 9 February 1941. Her husband went missing in action on 30 November 1941, on his way back from a bombing raid over Nazi Germany.
Mitford threw herself into war work. Through this, she met and married the American civil rights lawyer Robert Treuhaft in 1943 and eventually settled in Oakland, California. She became an American citizen in 1944.
There, the couple had two sons; Nicholas, born in 1944 (who was killed in 1955 when hit by a bus), and Benjamin, born in 1947. Mitford approached her motherhood in a spirit of "benign neglect", described by her children as "matter-of-fact" and "not touchy-feely". She became closer to her own mother by letter over the decades but remained estranged from her sister Diana for the rest of her life.
Mitford spent much of the early 1950s working as executive secretary of the local Civil Rights Congress chapter. Through this and her husband's legal practice, she was involved in a number of civil rights campaigns, notably the failed attempt to stop the execution of Willie McGee, an African-American convicted of raping a white woman. Mitford and Treuhaft became active members of the Communist Party. In 1953, at the height of McCarthyism and the 'Red Scare', they were summoned to testify in front of the House Un-American Activities Committee. Both refused to testify about their participation in radical groups.
In 1956, Mitford published (stenciled) a pamphlet, "Lifeitselfmanship or How to Become a Precisely-Because Man". In response to Noblesse Oblige, the book her sister Nancy co-wrote and edited on the class distinctions in British English, popularizing the phrases "U and non-U English" (upper class and non-upper class), Jessica described L and non-L (Left and non-Left) English, mocking the clichés used by her comrades in the all-out class struggle. (The title alludes to Stephen Potter's satirical series of books that included Lifemanship.)
Feeling that in the current political climate they could do more for social justice outside the Party, and disillusioned by the development of communism in the Soviet Union, Mitford and Treuhaft resigned from it in late 1958.
In 1960 Mitford published her first book Hons and Rebels (US title: Daughters and Rebels), a memoir covering her youth in the Redesdale household.
In May 1961 she traveled to Montgomery, Alabama, while working on an article about Southern attitudes for Esquire. While there, she and a friend went to meet the arrival of the Freedom Riders and became caught up in a riot when a mob led by the Ku Klux Klan attacked the civil rights activists. After the riot, Mitford proceeded to a rally led by Martin Luther King, Jr. The church at which this was held was also attacked by the Klan, and Mitford and the group spent the night barricaded inside until the violence was ended by the National Guard.
Through his work with unions and death benefits, Treuhaft became interested in the funeral industry and persuaded Mitford to write an investigative article on the subject. Though the article, "Saint Peter Don't You Call Me" published in Frontier magazine, was not widely disseminated, it caught considerable attention when Mitford appeared on a local television broadcast with two industry representatives. Convinced of public interest, she wrote The American Way of Death, which was published in 1963. In the book Mitford harshly criticized the industry for using unscrupulous business practices to take advantage of grieving families. The book became a major bestseller and led to Congressional hearings on the funeral industry. The book was one of the inspirations for filmmaker Tony Richardson's 1965 film The Loved One, which was based on Evelyn Waugh's short satirical 1948 novel of the same name, tellingly subtitled "An Anglo-American Tragedy".
After The American Way of Death Mitford continued with her investigative journalism. In 1970, she published an article in the Atlantic Monthly, "Let Us Now Appraise Famous Writers", an exposé of the Famous Writers School, a correspondence course of questionable business practices founded by Bennett Cerf. She published The Trial of Dr. Spock, the Rev. William Sloane Coffin, Jr., Michael Ferber, Mitchell Goodman and Marcus Raskin, an account of the five men's 1970 trial on charges of conspiracy to violate the draft laws, followed by a harsh critique of the American prison system entitled Kind and Usual Punishment: The Prison Business (1973), an allusion to the phrase "cruel and unusual punishment".
Mitford was a distinguished professor for the fall semester 1973 at San Jose State University, where she taught a course called "The American Way" that covered the Watergate scandal and the McCarthy era. Because of disagreements with the dean over her taking a loyalty oath and submitting to fingerprinting, the campus was thrown into protests and she was forced to go to court to remain able to teach.
Mitford's second memoir, A Fine Old Conflict (1977), comically describes her experiences joining and eventually leaving the Communist Party USA. Mitford titled the book after what, in her youth, she thought were the lyrics to the Communist anthem, "The Internationale", which actually are "Tis the final conflict". Mitford recounts how she was invited to join the Communist Party by her co-worker Dobby, to whom she responded "We thought you'd never ask!" She bristled against the conservative structure in the CP, at one point upsetting the women's caucus by printing a poster with "Girls! Girls! Girls!" to draw people to an event. She mercilessly teased an elder Communist about what she perceived as his paranoia when he wrote out the name of a town where she could get chickens donated from "loyal party members" for a fund raiser. When he wrote Petaluma on a scrap of paper to avoid being overheard by possible bugs, she asked in jest how the chickens should be prepared, and wrote, "Fried or broiled".
In addition to writing and activism, Mitford tried her hand at music as singer for "Decca and the Dectones," a cowbell and kazoo orchestra. She performed at numerous benefits and opened for Cyndi Lauper on the roof of the Virgin Records store in San Francisco. She recorded two short albums: one contains her rendition of "Maxwell's Silver Hammer" and "Grace Darling", and the other, two duets with friend and poet Maya Angelou. Her last work was an update entitled The American Way of Death Revisited.
Mitford died of lung cancer aged 78. In keeping with her wishes, she had an inexpensive funeral, costing $533.31 – she was cremated without a ceremony, her ashes scattered at sea, the cremation itself costing $475. At the time of her death, the San Francisco Chronicle columnist Herb Caen wrote "In this strangely flat era of 'diversity,' she was the rarest of birds, an exotic creature who rose each morning to become the sun around whom thousands of lives revolved."
Her widower survived her by five years. Her surviving daughter continued the activist tradition, working for the Student Nonviolent Coordinating Committee. She had two children with James Forman, the committee director, and eventually became an emergency room nurse.
The author Christopher Hitchens expressed his admiration for Jessica Mitford and praised Hons and Rebels.
J. K. Rowling, author of the Harry Potter series, stated in 2002:
Rowling reviewed Mitford's book of letters, Decca, in the Sunday Telegraph in 2006.
In 2013 the singer David Bowie named The American Way of Death as one of his favorite books."Objectivity? I've always had an objective."
"You may not be able to change the world, but at least you can embarrass the guilty."
"Gracious dying is a huge, macabre and expensive joke on the American public."
At a museum exhibit on Egyptian embalming: "Now THERE is a culture where the funeral directors REALLY got out of hand!" (Said to Molly Ivins at the Houston Funeral Service Museum in 1995. Reported in Decca: The Letters of Jessica Mitford, p. 691)
When Evelyn Waugh wrote in a review of The American Way of Death that Mitford did not have "a plainly stated attitude to death", Mitford asked her sister Deborah to tell Waugh: "Of course I'm against it."
Nancy Mitford (28 November 1904 – 30 June 1973)
Pamela Mitford (25 November 1907 – 12 April 1994)
Thomas Mitford (2 January 1909 – 30 March 1945)
Diana Mitford (17 June 1910 – 11 August 2003)
Unity Mitford (8 August 1914 – 28 May 1948)
Jessica Mitford (11 September 1917 – 22 July 1996)
Deborah Mitford (31 March 1920 – 24 September 2014)
Extracts from Decca: The Letters of Jessica Mitford were dramatized for Book of the Week, BBC Radio 4, five 15-minute programmes broadcast in November 2006. The readers were Rosamund Pike and Tom Chadbon; the producer was Chris Wallis.