Merle Haggard has recorded literally hundreds of albums and thousands of songs in his career, and at age 72 he shows no signs of slowing down. He's released 11 albums in the last decade — everything from an album of honky-tonk classics to duets with George Jones and a bluegrass disc recorded mostly live in the studio. Put on any of Haggard's 38 Number One songs and you'll immediately understand why he's one of the most important singers and songwriters in American pop music history. But with this playlist of my personal favorites, I've tried to focus on a more intimate of Haggard — the songs that chart his evolution as a songwriter and also as an individual.

The list starts with his first significant hit, "All My Friends Are Gonna Be Strangers," and ends with two tracks from his 2007 bluegrass album, both of which give a sense of the deep vulnerability and grace in his later music. In between are big hits and heartbreakers and oddities — everything from his tribute to Texas swing legend Bob Wills to his stellar duet with Willie Nelson on Townes Van Zandt's "Pancho and Lefty." It's 40 years of mind-blowing music that only scratches the surface of a true American hero.

Jason Fine's "The Fighter: The Life and Times of Merle Haggard" appeared in Issue 1088 of Rolling Stone. Also check out a career-spanning photo gallery tracking the life of the badass legend.

"(All My Friends Are Gonna Be) Strangers"

"Fugitive"
In 1966, Haggard had his first Number One song with Anderson's "The Fugitive." The song was about a TV show popular at the time, but it hinted at Haggard's story: "I raised a lot of Cain back in my younger days/While Mama used to pray my crops would fail/Now I'm a hunted fugitive with just two ways/Outrun the law or spend my life in jail."

Though he sang about outlaws, Haggard was terrified to let people know about his own criminal past. "The last thing in the world I wanted to do," he says, "was walk up like David Allan Coe and say, 'Hey, I've been to prison, look at me.' " "The amazing thing about Merle," says Kristofferson, "is that he's never said, 'I'm the real thing, and these other guys are just going through the motions.' " It was Cash who eventually persuaded Haggard to talk about his past on Cash's TV show in 1969: "He told me, 'They're going to find out anyway. If you own up to it, you'll be a hero.' "