Forty years ago, in April 1978, Willie Nelson released Stardust. An album of pop standards, it became the best-selling record of his career and cemented his status as a musical iconoclast; at the time, however, it wasn't necessarily an obvious career move.

In the late '70s, Nelson was in the midst of a commercial hot streak that had kicked off with 1975's Red Headed Stranger, and he was a reliable country music star. Stardust, however, featured covers of songs by Hoagy Carmichael, George and Ira Gershwin and Duke Ellington, and took influences from jazz ("Blue Skies," "All of Me"), pop (the hushed "Unchained Melody") and folk (the string-sugared title track).

To make Stardust, Nelson turned to an unexpected collaborator: his Malibu neighbor, Booker T. Jones, who first found fame with the soul / R&B / funk pioneers Booker T & the MGs. The icon served as Stardust's producer, as well as its music supervisor / arranger. Nelson initially asked Jones to arrange the song "Moonlight in Vermont" for him, and he liked the results so much that he decided a full-scale collaboration was in order.

"For all our differences, Booker and I were linked by our love of the blues in general, and our love of Ray Charles in particular," Nelson wrote in his 2015 autobiography, It's A Long Story: My Life. "When I had just the slightest hesitation about singing "Georgia on My Mind," a song so closely associated with Ray, Booker encouraged me. 'Ray did it his way,' he said, 'and you'll do it yours. None of these songs belong to any particular singer. They belong to the world.'"

Columbia

To create Stardust, Nelson hunkered down in a Hollywood Hills home studio in early December of 1977 with a stable of familiar faces: guitarist Jody Payne, bassist Bee Spears, drummers Paul English and Rex Ludwig, his sister Bobbie on piano and Mickey Raphael on harmonica (and Jones, of course, also contributed piano and organ). Nelson noted in It's A Long Story: My Life that he made the record in "little more than a week," but added, "I never felt rushed. I had lots of space to maneuver and calmly meditate on the meaning of these timeless songs. I had lots of time to caress the melodies in my own way. I had the freedom to let my guitar say what needed to be said."

Stardust is a luxurious album full of gorgeous, deeply felt instrumental detailing: twinkling percussion, understated drums, ornate guitars, jaunty piano, Raphael's mournful harmonica and, of course, Jones' inimitable evocative organ. On the country-influenced take on "Someone to Watch Over Me," Jones' contributions in particular give the song gravitas.

Despite the attention to detail, Nelson's label, Columbia, was wary about the project, specifically its older source material. According to the musician's autobiography, the label wanted a separate producer to buff up the songs for the radio, and insisted that Nelson's fans wanted to hear him singing "edgy cowboy songs. Or Grateful Dead or Bob Dylan songs ... Believe me, they don't want to hear you doing songs they associate with their fathers or grandfathers."

But Nelson stuck to his guns -- and followed his heart -- and released Stardust as it was. His intuition was correct: The album hit No. 1 on the country charts (and No. 30 on the overall Billboard Top 200) and spawned three Top 5 country singles hits, including two chart-toppers ("Blue Skies," "Georgia on My Mind") and the No. 3 smash "All of Me."

Over the years, Stardust has remained popular as well. A 1999 CD reissue tacked on two bonus tracks, while a 30th anniversary edition of the album with a bonus disc of standards arrived in 2008. But although Nelson was happy with the positive critical reception to Stardust, he was even happier about the freedom the LP afforded him.

"What pleased me most was the damage done to narrow-minded thinking," he wrote in It's A Long Story: My Life. "Conventional wisdom said that country music fans wouldn't go for pop standards, and it insisted that my new young audience wouldn't go for old songs. Wrong on both counts. Stardust broke down barriers and busted up categories. Its blockbuster sales success put me in a position where I never had to argue with record execs again. From then on, without discussion, I just kept recording what came to me naturally, without forethought or analysis."

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