Ken Burns photographed at Harris Concert Hall in August.
Lynn Goldsmith

In Ken Burns’ editing room hangs a neon sign that reads “It’s Complicated.”

The motto has held true across the wide swath of American history the documentarian has covered and certainly does on his latest series for PBS, “Country Music,” which begins airing Sunday night.

The eight-part, 16-hour series details a surprisingly complicated history of the genre with Burns’ signature depth of archival research, rarely seen photos and original interviews.

Burns himself was blown away by revelations big and small, from how some of country’s most iconic songs came into being to the central roles that women and African-Americans played in the story of country music.

“That’s why this isn’t just a K-tel record offer, it’s not the TimeLife country music series – this is a story,” Burns said backstage at Harris Concert Hall last month, before a preview of the film hosted by the Aspen Music Festival and School.

The documentary tracks the history of country from the early 20th century and the days of the Carter Family through the 1990s and the superstardom of Garth Brooks, who defines country music as “three chords and the truth.”

Along the way it traces the music’s role in American culture and counterculture, the evolutions of its sound as well as its place in gender equality and race relations.

Country music has been intertwined with Burns’ work seemingly from the beginning of his career and his 1988 documentary on the painter Thomas Hart Benton, so it’s a surprise it took him until nearly four decades into his filmmaking career to tackle it.

“It couldn’t have happened a moment sooner and I’m happy we didn’t start it a moment later,” Burns said.

A self-proclaimed “child of R&B and rock’n’roll,” Burns was not a country music fan before this undertaking, which spanned eight years of production. Making the film, however, converted him.

“I was completely unprepared,” Burns said. “It shattered every preconception I had.”

The film is arriving into a moment of cultural debate about country and its preconceptions as a regressive artform for and by straight white men. Sunday’s premiere comes on the heels of “Old Town Road” — a country song by the black, gay rapper Lil Nas X — breaking the record as the longest reigning No. 1 charting song in history. The song’s success and its unorthodox approach to the country sound underscore the film’s thesis that country is – and always has been – more complex and inclusive than it might seem.

“Thanks to Lil Nas X for walking onto the stage and preparing our audience for us,” Burns said. “We don’t have to prepare anybody or worry about, ‘Oh, here’s Burns again with his race thing.’”

Every episode of the series touches on issues of race in country music. It includes sections focused on the banjo, which descended from African instruments that were brought to the U.S. by slaves, on how early country was built from a foundation of spirituals and field songs, and on the fascinating evolution of the melody in Woody Guthrie’s “This Land Is Your Land” back to the Carter Family’s “Little Darling, Pal of Mine” to its original source material as a black church hymn.

Kris Kristofferson calls country “the white man’s soul music” in the film, but Burns seems to make an argument against that definituon. His film highlights the contributions of African-American artists who have been written out of history, the integration of country music recording sessions as early as the 1920s and it devotes an extended segment to the mid-1960s stardom of Charley Pride.

“Nobody ever believes it, but every time I finish a film it seems to be exactly what the culture wants at that moment,” he said.

Each episode also highlights the centrality of women to the country music form, from Maybelle Carter through the trailblazing proto-feminist songs of Loretta Lynn. Burns said he was personally most moved by the story behind Dolly Parton’s “I will Always Love You,” which she wrote to get out from under the thumb of her manipulative and controlling creative partner Porter Wagoner.

“Women will look at this film and not believe it was editorially done before the #MeToo movement,” Burns said.

Aspenites will take particular interest in the sixth part of the series, which digs into the early days of the Nitty Gritty Dirt Band. The segment focuses on the making of the band’s watershed 1972 triple album, “Will the Circle be Unbroken,” and how it brought together an older and more conservative generation of country music fans with the hippie kids of the day.

The section includes dozens of photos of the band’s historic six-day Nashville recording session, showing a baby-faced Jimmy Ibbotson alongside country-western legends like Maybell Carter, Earl Scruggs and Roy Acuff, and includes interviews with Dirt Band members John McEuen and Jeff Hanna.

“For us, it was like going back to 1928 and making an old record,” John McEuen says in the film. “We wanted to make an old record.”

“Country Music” is built on seemingly comprehensive research, including 101 interviews, 1,000 hours of film and some 100,000 photographs, culled down to the 3,300 featured in the final product.

Twenty of the interview subjects in the film have since died, including some of the final on-camera interviews with Merle Haggard, Ralph Stanley, and the series standout Hazel Smith – a folksy and blunt-spoken woman who served as an office manager to Willie Nelson and The Outlaws during their mid-1970s heyday.

Burns’ research for “Country Music” overlapped with his 2017 documentary on the Vietnam War, and with forthcoming films on Ernest Hemingway and Muhammad Ali.

“They talk to each other all the time,” he said of his always-full slate of projects.

Burns has four production teams that work on films simultaneously, so he is constantly hopping between seemingly disparate topics for films in various stages of development. For example, Burns was leaving the editing room of “The Vietnam War” to shoot interviews for “Country Music,” and he’s now early in editing the Hemingway film and finalizing his voiceover scripts for the Ali project while he’s out promoting “Country Music,” all while he’s early stages of films on Benjamin Franklin and the Revolutionary War.

“It’s a tapestry,” he said. “It’s all woven together.”

Every project informs the other and deepens his understanding of American culture. He’s made 15 films that cover the U.S. in the 1920s, he noted, and as he put it, “It’s always a different ’20s. The flappers show up, the gangsters show up, but the other stuff underneath – whether it’s ‘Jazz’ or ‘Baseball’ or ‘Country Music’ or ‘The Roosevelts’ – it’s a different ‘20s. It’s wonderful. I didn’t think you could wring that much information out of something.”

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