In your memory, Louisa May Alcott’s “Little Women” may linger as a charming, occasionally heartbreaking story of four sisters growing up in the years during and after America’s Civil War, guided by a generous, loving mother.

But the story of the March girls isn’t so simple, according to author Anne Boyd Rioux. The book is about young women coming of age at a time when a woman’s appearance is valued more than her mind (some things never change). It doesn’t reflect a perfect family but one on the verge of being torn apart. And if this story is a celebration of the joys of girlhood, Rioux asks, why does it focus on “a girl who doesn’t want to be one at all?”

It’s an excellent question, one Rioux considers with intelligence and insight in “Meg, Jo, Beth, Amy: The Story of ‘Little Women’ and Why It Still Matters.” With impeccable research and genuine affection, she charts the history of the beloved (and sometimes reviled) novel, tracing its origins from the pen of reluctant Alcott to its No. 8 spot in a 2014 Harris Poll of Americans’ favorite books of all time.

“Little Women,” which has never gone out of print, celebrates its 150th anniversary this year. If you’re counting, that’s 150 years of girls daydreaming about being Jo March, who rebels against society’s demands and longs to be a writer. Do readers ever identify with any character but Jo? Rioux seems to think so, but doubt on that score seems reasonable, especially when she lists writers who idolized the tomboy, including Jane Smiley, Barbara Kingsolver, Nora Ephron, Anne Lamott, Bich Minh Nguyen and Cynthia Ozick.

That’s also 150 years of weeping over the death of shy sister Beth, and 150 years of frustration over Jo’s marriage to Professor Bhaer – because isn’t he just so old and, anyway, what was wrong with Laurie, the boy next door? And how did that “niminy piminy chit” Amy – Alcott’s words – end up married to him?

Author of the biography “Constance Fenimore Woolson: Portrait of a Lady Novelist” and a professor at the University of New Orleans, Rioux confesses that she first read the book in her 20s, which inevitably colors her interpretation of it, though not to any detriment.

In “Meg, Jo, Beth, Amy” she covers an intriguing set of topics, from the book’s reception in 1868 to its current representations in pop culture (a new feature film, the fifth, is due next year from “Ladybird” director Greta Gerwig). Alcott doubted anyone would care about her book, but young fans clamored for more. Nobody had written a book about girls’ lives without a lot of fuss about morality. Most literature for children was “stilted and pious,” Rioux writes, the artificial stories “told by wise adult narrators talking down to children, warning them to be obedient.” By contrast, “Little Women” felt fresh and realistic.

Rioux reports on the familiar notes of Alcott’s life, including the family’s poverty, her long-suffering mother, her idealistic but absent father, the death of her sister Lizzie. The history adds important context, but “Meg, Jo, Beth, Amy” is most riveting when Rioux explores the novel’s cultural relevance and examines its adaptability as a text. “Little Women” has been used, for example, to tout conservative and progressive messages: “It points backward to a simpler time of family cohesion and looks forward to a complicated time when women would find work away from home and family.”

Still, questions remain. How do we get boys interested in reading “Little Women”? Can Jo March compete with Harry Potter and other modern fantasy fiction? “Little Women” is already fighting a battle for the attention of contemporary children: While adults say it’s a favorite, “hen kids themselves are asked what they are reading, ‘Little Women’ doesn’t even register.”

Rioux’s simple solution? Publish the book in two parts again instead of as one giant, intimidating novel.

But despite this declining interest in “Little Women” by young readers, Rioux persuasively argues that Alcott’s influence remains: “Instead of growing up with Jo March, girls are growing up with a host of new literary heroines who are clearly descended from her.” Who is Katniss Everdeen but Jo March with a bow and arrow? Women may forge more independent lives now, but strong role models are still necessary. “Until girls’ stories are truly able to follow the lead of ‘Little Women,'” Rioux believes, “Meg, Jo, Beth, and Amy will continue to live and challenge us.”