As plans came together for a 90th-birthday concert for Pete Seeger at Madison Square Garden, Bruce Springsteen, John Mellencamp, Dave Matthews and four dozen other artists jumped onboard — but the folk legend needed persuading. "Normally, I'm against big things," Seeger said backstage at the May 3rd event, which raised money for Seeger's Hudson River Sloop Clearwater foundation. "I think the world's going to be solved by millions of small things." He was ultimately won over by his grandson Tao Rodriguez-Seeger, who told him, "We can put together a concert for 18,000 people where everyone will feel like everyone else's neighbor, and everyone will sing along and feel that healing bond."
Seeger's career as a musician and activist goes back to the Thirties and Forties, when he sang with Woody Guthrie — but his influence may have peaked in the Sixties, when he was a key figure in the folk revival, even as he was banned from TV and many venues in a Red Scare blacklist. And it was the Sixties spirit that prevailed at the celebration. "Pete was definitely a founding father of the whole hippie thing," says Roger McGuinn, who was hacked by members of Band of Horses as he sang the Byrds' version of Seeger's "Turn! Turn! Turn!"
Strangers held hands as an all-star group that included Joan Baez and Billy Bragg sang "We Shall Overcome," and the audience erupted at the opening notes of Richie Havens' Woodstock anthem "Freedom." The show ended with all of the night's performers — including a spry, beaming Seeger — onstage for "This Little Light of Mine" and "Goodnight Irene," best known as a Number One hit for Seeger's Fifties group the Weavers. "Pete hasn't lost a step," says Kris Kristofferson, who sang "Hole in the Bucket."
Backstage, artists spanning generations and genres — the performers ranged from Tom Morello and Ben Harper to Emmylou Harris and Steve Earle — praised Seeger as an essential inspiration. Baez and Matthews each recalled their families taking them to his concerts as kids. "My parents sneakily devised a plan to get me away from the blues, so they spirited me away to a concert of Pete Seeger's, and it was like a vaccine that took," says Baez. Adds Matthews, "He was my first concert, and I remember it well. He represents a pretty uniquely righteous kind of person, and it would be better if there was more of them around."
In Seeger's collaborative spirit, the night was full of artist pairings. Morello was a frequent presence onstage: He sang Seeger's anti-war song "Waist Deep in the Big Muddy" with Taj Mahal and later accompanied Springsteen on "The Ghost of Tom Joad." "The history of Pete's life is the history of music changing the world," Morello says. Onstage, Springsteen hailed the inspiration for his Seeger Sessions album and tour as a "living archive of America's music and conscience": "Pete, you outlasted the bastards, man," he said, remembering that Seeger was determined to sing the oft-omitted final verses of "This Land Is Your Land" at the Obama inauguration concert on the Mall, in Washington, D.C. "Of course, that's what Pete's done his whole life. He sings all the verses all the time especially the ones that we would like to leave out of our history as a people."
Mellencamp opened the show with the first song he had learned to play as a child, Seeger's "If I Had a Hammer," before playing his own Seeger-inspired "A Ride Back Home." "Pete Seeger has been in my life as long as I can remember," says Mellencamp, adding that seeing Seeger still playing at 90 was a powerful experience. "I'm trying to find a way to be age-appropriate with what I do and it gives you inspiration to see somebody like that."
This story is from the May 28, 2009 issue of Rolling Stone.