Perhaps America’s greatest annual music festival celebrated its 50th installment a couple of years back, and promptly went on hiatus for two years, thanks to COVID.

The New Orleans Jazz & Heritage Festival came back this year, and hot on its heels comes “Jazz Fest: A New Orleans Story,” a documentary about how the festival came to be, an essay on a city and its musical history built on musical highlights of that 50th anniversary event, and a film that finishes with a bit of its triumphant return in 2022.

Co-directors Ryan Suffern (the recent “How Can You Mend a Broken Heart” Bee Gees doc) and celebrated producer/director Frank Marshall take us onstage with the performers and catch up with scores of the folks who made and continue to make this epic gathering of hundreds of thousands happen, and backstage for this thorough overview of what makes the Jazz & Heritage Festival a singular event.

It’s “the world’s greatest backyard party” set in “the only unique city in America,” featuring a multi-national/multi-cultural musical gumbo on stage, and the culinary delights of a legendary food town — gumbo included — everywhere else at the city’s Fairground Race Course every spring.

It was first proposed during the “Jim Crow” 1960s, founder George Wein recalls, but didn’t come to life until “that changed.” The idea? Feature the music of the city, the people of the city and its food, “and the world will come.”

Damned if the world didn’t.

As one enthusiast declares, “Everybody eats and everybody dances,” and Jazz Fest — featuring jazz, pop, zydeco, World Music, funk, blues, rock, gospel and pop (check out Katy Perry in her winged spacesuit bustier joining a huge Gospel choir for “Oh Happy Day”) hurls them all together for a week of thousands of singers and musicals and tens of thousands of fans.

Exhibit A in the show’s cross-cultural appeal might be Caribbean-influenced country-pop star Jimmy Buffett, “consistently, our biggest draw” longtime director Quint Davis enthuses, bringing huge crowds of older white “yacht rock” Parrotheads into an environment where “passing from stage to stage, you can’t help but be exposed” to unknowns, local legends, African acts and African American Gospel choirs.

Pitbull marvels at the food and audience blend and its connection to his Cuban heritage — “I think all our arteries will get clogged (Jazz Fest) day!” The Marsalis family and other members of New Orleans music royalty take to the stage to pay tribute to their father, Ellis, playing with him one last time, Boyfriend brings her loopy stage show in and Trombone Shorty brings down the house, year after year.

Everything about the event “is still handmade” Davis insists, something that became obvious after Hurricane Katrina almost washed the city away, and again after COVID shut the festival down for two years.

The film captures the essence of an event that “ties the city together,” with Bruce Springsteen showing up among many others after Katrina to re-launch the festival, Rev. Al Green choosing Jazz Fest to return to public (secular) performance and Mr. “Margaritaville” welcoming the world back to New Orleans as the pandemic subsides.

A real music lover’s treat, this film.

Rating: PG-13 for brief language and some suggestive material

Cast: Interviews and performances with Pitbull, Jimmy Buffett, Samantha Fish, Brnaford Marsalis, Trombone Shorty, Al Green, George Wein, Big Freedia, Tarriona “Tank” Ball, The Revivalists, Quint Davis and many others.

Credits: Directed by Frank Marshall and Ryan Suffern. A Sony Pictures Classics release.

Running time: 1:35