The rock world lost one of its most beloved cult heroes when Warren Zevon died on Sept. 7, 2003, after a year-long bout with lung cancer. He was 56.

Zevon had been feeling the symptoms – including dizziness and shortness of breath – leading up to his stint at the Edmonton Folk Music Festival in August 2002. Zevon had long had a fear of doctors, but had no choice but to go for a check-up after returning home. The diagnosis was inoperable mesothelioma, a form of cancer that develops as a result of exposure to asbestos.

He went to work with longtime friend and collaborator Jorge Calderon on what he knew would be a final musical statement, The Wind. Old friends such as Bruce Springsteen, Jackson Browne and Tom Petty made guest appearances, and a VH1 documentary crew filmed the sessions. The album was released on Aug. 26, only 12 days before Zevon's death.

But something else from his past also came back.

Zevon had been sober since the mid-'80s, when a long stint in rehab finally took hold after several previous attempts failed. With death imminent, however, Zevon began drinking again the night of the engagement party for his daughter, Ariel.

David Letterman Gave Him a Big Honor

"I got very angry with him during that period, and I never told him," writer Carl Hiaasen said in I'll Sleep When I'm Dead: The Dirty Life and Times of Warren Zevon, an oral history by Zevon's ex-wife's Crystal. "I didn't have the heart to because of what he was going through. I could understand the depression, but this was extraordinarily selfish behavior for someone when you have your kids, and their hearts are already breaking, and then to have to see your father like this. ... He knew that. He knew it very well. He wasn't proud of what he was doing."

David Letterman also found a way to honor Zevon, a frequent guest who occasionally filled in for bandleader Paul Shaffer. Zevon was The Late Show's only guest on Oct. 30, 2002, and performed three songs, "Genius," "Mutineer" and "Roland the Headless Thompson Gunner."

READ MORE: The Song That Made Warren Zevon Swear Off Vacations

He was expected to die within a few months of his diagnosis, but Zevon lived long enough to see the birth of his twin grandsons, Gus and Max. He approached his death with the same gallows humor that infused his songs.

"When Warren finished recording The Wind," Crystal said, "he called me and said, 'I better die quick so they'll give me a Grammy nomination. It's a damned hard way to make a living, having to die to get 'em to know you're alive.'"

Warren Zevon Albums Ranked

A songwriter's songwriter covered by everyone from Linda Ronstadt to Bob Dylan, he never lost his caustic wit, even when knocking on heaven's door.

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