After all the musicians — including Katy Perry, Miley Cyrus, Justin Bieber, Coldplay and Pharrell Williams — left the stage Sunday night at One Love Manchester, Ariana Grande walked back out, blowing kisses to the crowd.

She began to sing “Over the Rainbow,” an optimistic coda for a tribute concert to the 22 killed and more than 55 injured by a terrorist attack at her May 22 show in Manchester. Halfway through, her voice faltered with emotion.

The concertgoers, so recently touched by tragedy, remained mostly silent as they waved their lit phone screens in the night sky, just as people held lighters 20 years earlier. Several audience members cried as Grande’s voice soared with lyrics that have stood for hope for some eight decades.

Someday I’ll wish upon a star
And wake up where the clouds are far
Behind me
Where troubles melt like lemon drops

The song was first written for the 1939 film “The Wizard of Oz” and sung by Judy Garland’s Dorothy before visiting the enchanted land of Oz.

Prolific American composer Harold Arlen wrote the music. And Yip Harburg — a liberal so outspoken on issues of gender, race and workers’ rights he earned the nickname “Broadway’s social conscience” — penned its brief but everlasting lyrics.

Harburg, the son of Russian Jewish immigrants, was born as Edgar Yipsel Harburg into extreme poverty in 1896 on New York City’s Lower East Side. Like so many Jewish immigrant children in New York, he attended City College, along with high school classmate Ira Gershwin. The pair often wrote poems together.

But Harburg considered writing something done “for fun, a sideline,” and decided to go into the electrical supply business to claw his way out of poverty. He mostly succeeded until the Great Depression, which financially devastated him.

“For the next few years we made a lot of money and I hated it,” Harburg once said. ”But the economy saved me. The capitalists saved me in 1929, just as we were worth, oh, about a quarter of a million dollars. Bang! The whole thing blew up. I was left with a pencil and finally had to write for a living. As I told Studs Terkel once, what the Depression was for most people was for me a lifesaver!”

He began writing song lyrics, and most of them, especially “Over the Rainbow,” carried political messages speaking to what he perceived of as a better world.

“No one wrote about more controversial subjects, from poverty and racism to women’s rights and the atomic bomb, than Harburg. Yet he did it with pixie-like glee, using laughter to make his pointed observations about the nightmares of the modern world,” Thomas S. Hischak wrote in “Boy Loses Girl: Broadway’s Librettists.”

“We worked for in our songs a sort of better world, a rainbow world,” Harburg once said. “Now, my generation unfortunately never succeed in making that rainbow world, so we can’t hand it down to you. But we could hand down our songs, which still hang on to hope and laughter … in times of confusion.”

That particular song has indeed become an anthem of hope, particularly in the face of hatred, fear and death. Though its original lyrics spoke to the struggle Americans faced in the Great Depression, they were malleable enough to connect with any cause.

As part of the public-private V-Disc program, a recording of the song by Judy Garland and the Tommy Dorsey Orchestra was shipped to soldiers serving in World War II, the Times Union reported. Meanwhile, it became an “anthem” for the LGBT community, even partially inspiring the rainbow flag. As Ben Brantley wrote in the New York Times:

Her version of “Somewhere Over the Rainbow” became an anthem of pain for homosexuals who perceived themselves as belonging to a despised minority. Her interpretation of the song seemed, as a character in “Judy at the Stonewall Inn” puts it, to embody “all the suffering voices of the world twisted into one spectral shape.”

The song often appears in the face of tragedy. The Sandy Hook Elementary choir, for example, recorded a version in the aftermath of the school’s 2012 mass shooting. NASA even used it as a wake-up call for astronauts on the first space shuttle mission to the International Space Station

Harburg’s son Ernie, who wrote his father’s biography, “Who Put the Rainbow in The Wizard of Oz?: Yip Harburg, Lyricist,” believes one particular word choice is what made the song so enduring, as he explained in an interview with Democracy Now:

It’s a story of a little girl that wants to get out. She’s in trouble, and she wants to get somewhere. Well, the rainbow was the only color that she’d see in Kansas. She wants to get over the rainbow. But then, Yip put in something which makes it a Yip song. He said, “And the dreams you dare to dream really do come true.” You see? And that word “dare” lands on the note, and it’s a perfect thing, and it’s been generating courage for people for years afterward, you know?

It expressed “a poignant yearning for escape,” as the Library of Congress said when it selected the song for preservation in the National Recording Registry. The Recording Industry of America and the National Endowment for the Arts chose it as the top entry on their “Songs of the Century” list.

As Garland herself said in 1967, after all, “It represents everyone’s wondering why things can’t be a little better.”

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