The monthlong return of “Wicked” to Minneapolis’ Orpheum Theatre starting Wednesday means young girls from across the Upper Midwest will dress up in parent-approved princess costumes and attend their first live musical.

They also are doing their part to ensure that L. Frank Baum’s groundbreaking novel about Oz remains one of the most influential works of American literature.

“There’s no question that it’s at the top,” said renowned literary scholar Michael Patrick Hearn, who has written extensively about Baum. “ ‘Huckleberry Finn,’ ‘Little Women’ and ‘Tom Sawyer’ certainly have affected American life, but not like ‘The Wonderful Wizard of Oz.’ Probably the only thing you can compare it to these days is the Harry Potter madness.”

The difference, of course, is that Baum’s novel was published 117 years ago, yet it still casts a spell as powerful as anything J.K. Rowling has conjured.

“Wicked,” which imagines the origins of the sibling rivalry between Baum’s territorial-minded witches, is one of Broadway’s all-time greatest hits and has visited the Twin Cities five times, including a record-breaking run in 2006. “The Wiz,” an African-American musical adaptation of Baum’s story, drew more than 11 million viewers when it aired live on NBC two years ago and promises to be a highlight of Children Theatre’s upcoming season.

And then there’s the 1939 film, an initial box-office disappointment that bloomed into a perennial holiday treat after it started airing annually in the 1950s on television. That tradition stopped in 1991 — it now airs sporadically on TCM — but the film’s popularity has not waned.

At the Judy Garland Museum in Grand Rapids, Minn., the late actress’ hometown, visiting second- and third-graders are asked whether they’ve seen the movie. Roughly eight out of 10 raise their hands.

“It’s almost a rite of passage,” said the museum’s executive director, John Kelsch. “There are three things to remember about the ‘Wizard of Oz’: It’s timeless, timeless, timeless.”

The same could be said about the movie’s Oscar-winning tune, “Over the Rainbow,” named the defining song of the 20th century by the National Endowment of the Arts and the Recording Industry Association of America. Warren Buffett even warbled a version over the closing credits of a recent HBO documentary about him.

“It takes people back to the first time they saw the movie, maybe seeing it at holiday time with the family. It can’t help but bring back happy memories,” said Tony nominee Stephanie J. Block, who includes the Harold Arlen/Yip Harburg number in her cabaret act along with “Defying Gravity” from “Wicked.”

But the impact of Baum’s story has reached far beyond the blockbusters. Amazon’s “Lost in Oz: Extended Adventure,” an animated special aimed at children, was just nominated for five Daytime Emmys and will return later this year as a regular series. On the other end of the spectrum, NBC’s recent limited series “Emerald City,” a dark, violent sequel with Dorothy’s daughter subjected to various degrees of bondage, got a cold reception from viewers and critics.

More subtle ties to the Baum classic and its incarnations abound. Such lines as “Lions, tigers and bears, oh my!” and “Toto, I don’t think we are in Kansas in anymore” make the 1939 movie the most quoted this side of “Casablanca.” On a recent episode of FXX’s “It’s Always Sunny in Philadelphia,” the gang awakens after an electrical storm to discover they have been transformed into the cast of “The Wiz.” Rory’s farewell to her college chums in Netflix’s revival of “Gilmore Girls” nodded to Dorothy’s lingering goodbye to her ragtag companions.

“Baum created this extraordinary creative world,” said Mark Warshaw, an executive producer for “Lost in Oz.” “It’s a world where you have dark and light. You’ve got the wicked witches, but you also have the jolly Munchkins. And then you have Dorothy, who is a real problem-solver with an open heart who creates empathy with all the people she runs into along the way. That’s really fertile ground you can pull stories from.”

Dorothy’s odyssey

Lisa Von Drasek, curator of the University of Minnesota’s Children’s Literature Research Collections, points to Dorothy’s personal adventure as the most resonant draw.

“It’s a classic journey like ‘The Odyssey’ with fantastical elements like ‘Alice in Wonderland,’ ” she said. “Dorothy Gale’s journey is also an interior one of emotional growth. She finds that all she longs for can be already found within.”

The appeal was almost immediate. Baum’s novel was an overnight success, topping the list of bestselling children’s books for two years and spawning a touring musical so popular that it helped spur Baum to write 13 sequels.

Somewhere along the line, a theory developed that the novel was actually a commentary on the rise of populism in American politics. Nonsense, Hearn said.

“Baum wasn’t interested in morals or teaching anything,” said Hearn, editor of “The Annotated Wizard of Oz.” “He wanted to write an answer to European fairy tales. He was only interested in entertaining children.”

Still, the book found a place in grown-up discussion, particularly in the gay community, where “a friend of Dorothy” became a coy euphemism for one’s sexual orientation.

Tison Pugh, whose books include “Innocence, Heterosexuality, and the Queerness of Children’s Literature,” notes the original cover for Baum’s book features the Tin Man and the Scarecrow gazing at each other while holding hands.

“It’s not what we would recognize as gay today, but you can see a lot of romantic images between the Scarecrow and the Tin Woodsman in the books,” said Pugh, an English professor at the University of Central Florida. “As for straight relationships in the series, Auntie Em and Uncle Henry are the primary one, and they’re not there for much of it.”

Garland herself became an icon for gays, who undoubtedly will make up a significant portion of the thousands of tourists who will flock to the Wizard of Oz Festival in Grand Rapids this June. The museum hopes to have a traveling exhibit dedicated to the actress and her most famous role ready by 2022, which would have been her 100th birthday.

But torchbearers aren’t just relying on tradition to keep Dorothy’s legacy alive. The Boomerang Channel will premiere the animated “Dorothy and the Wizard of Oz” in June. A sequel to 2013’s successful film “Oz the Great and Powerful” is in the works, as is a movie version of “Wicked.” New Line Studios is developing a horror flick based in Emerald City.

In other words, the end of the yellow brick road is nowhere in sight.

“France has the Mona Lisa, America has ‘The Wizard of Oz,’ ” Kelsch said. “It’s our national treasure.”