In She Come By It Natural, the journalist Sarah Smarsh tracks Dolly Parton’s trajectory from being reduced to “the punch line of a boob joke” to “a universally beloved icon”. Now, Parton, who turned 75 on Tuesday, commands centre stage, “where women of a certain age historically have gone unseen”.

The book was born in the turbulence of US politics in recent years. Not recognising the “hateful, sexist version” of the rural working class propagated by the press during the 2016 presidential election, Smarsh set out to paint a more nuanced picture in a series of pieces for the music magazine No Depression.

For Smarsh, the author of an award-winning memoir about her struggling family farm, Dolly Parton is the antithesis of Donald Trump: a “unifying balm” amid increasing divisiveness. Catching a concert in Kansas, Smarsh was struck by the diversity of Dolly’s fan base, from “proud rednecks” to drag queens.

Parton’s rise to fame is an irresistibly American rags-to-rhinestones story. Born as the fourth of 12 children on a farm in the foothills of the Great Smoky Mountains in Tennessee, she grew up with no indoor plumbing, electricity or running water. Inspired by her musical mother, she began composing songs at the age of six and recorded her first single at 13.

Despite formidable successes as a performer, businesswoman and philanthropist, Parton still considers herself first and foremost a songwriter. She has written about 3,000 songs and recorded 47 solo studio albums. “I may look like a show pony,” she wrote in an earlier work, “but I’m a workhorse.”

Parton resists the label of feminist and sidesteps politics. “More about walk than talk”, writes Smarsh, like many working-class women, she embodies “a living feminism”. Smarsh draws parallels with her own grandmother, a Dolly superfan born in similar circumstances who walked away from bad situations until she had secured a stable job and partner. Parton has never shied away from addressing the indignities faced by women: in her early “sad-ass songs”, as she dubbed them, recurring motifs “include hypocritical, violent, and even murderous men; women being used, neglected, and shamed; and dying children”.

Emboldened by the crossover success of “Jolene” in 1973, Parton’s first feminist act was breaking away from her business partner, Porter Wagoner, after seven years as the “girl singer” on his television show. Another savvy move was declining Elvis Presley’s request to record “I Will Always Love You” when he demanded half of the publishing rights — a decision that paid off handsomely when Whitney Houston’s 1992 rendition for the film The Bodyguard became the bestselling single by a female artist in history.

Like Parton herself, She Come By It Natural offers a rare mouthpiece for a demographic that often goes unheard — women who are working on their feet in restaurants and factories “while others are tweeting with their fingers”. Smarsh surmises that Parton continues to embrace a drag-like aesthetic of big wigs and acrylic nails out of respect for her roots.

Earlier in her career, Parton was perpetually subjected to sexualised comments from TV presenters; even female interviewers such as Oprah Winfrey and Barbara Walters asked her to stand up to display her figure. Ever-gracious, Parton often beat her interlocutor to the punchline. “All these years people [have] thought the joke was on me,” she told Walters in 1977, “but it’s actually been on the public. I know exactly what I’m doing.”

She Come By It Natural: Dolly Parton and the Women Who Lived Her Songs by Sarah Smarsh, One, £9.99/ Scribner $22, 190 pages

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