The man of the moment spent the day as he has spent every day for the past 26 years—in one of South Africa's maximum security prisons. Nothing could change that. But Nelson Mandela, the adversary of apartheid sentenced to life imprisonment for sabotage and conspiracy to topple the South African government, had some kind of 70th birthday party. When all was sung and done, more than a billion people in more than 60 countries—from Qatar to Ecuador, and Angola to Aruba—saw last Saturday's Freedomfest, the 11-hour London rock megaconcert dedicated to the man who symbolizes resistance to South Africa's racist policies. The extravaganza drew the largest audience for a music event in the history of television, and the promise of such unprecedented exposure of course helped coax super-celeb rock stars to forgo fees. But it was the cause that brought such an enthusiastic turnout of talent for the Wembley Stadium benefit. There was some controversy, some friction, but thanks to specially dedicated songs and political speeches, Artists Against Apartheid brought Mandela to the world's center stage.

Wembley's 180-foot-long, 80-foot-deep raised platform was decorated with outsize posters of Mandela. Harry Belafonte, who has just released an antiapartheid album, opened the show by addressing the absent prisoner. "The message is quite simple," the singer said. "We salute you, and we want to see you and your fellow prisoners free." Similar messages followed. Sting headed his set with "If You Love Somebody Set Them Free." Sporting a crucifix earring, George Michael, the ex-Wham! man, did a medley of soul tunes, explaining that it "was my duty, as a white singer, to perform black songs."

Yet the 72,000 ticket holders who forked over 50 bucks each to attend the show were not all proto-poli-sci professors. They wanted, and got, spectacle. When the Eurythmics' Dave Stewart and two-months-pregnant Annie Lennox lit into "Sweet Dreams Are Made of This," or when Chrissie Hynde struck up "I Got You Babe" with UB40, the frenzied reaction of fans shook the 175 tons of scaffolding erected for the event.

Artists Against Apartheid, organizers of the concert, was founded two years ago by Jerry Dammers, former vocalist of the British ska band the Specials. After hearing that Simple Minds' lead singer, Jim Kerr, had once called Nelson Mandela a symbol of all political prisoners worldwide, Dammers approached him with his plan for a tribute. Kerr enlisted Dire Straits. Sting and Peter Gabriel then signed on, and the project was cinched when Whitney Houston added her name. "It was an amazing coup that she wanted to come," says Kerr. "A hugely popular black artist really made it credible. I'd never have thought she'd take a political stance."

Onstage, Houston brought the house down with "Didn't We Almost Have It All," a tearful duet of "The Greatest Love of All" with her mother, Cissy, and "I Get So Emotional." Backstage, other performers got just as emotional over Houston's superstar behavior. Her bodyguards rudely shoved Whoopi Goldberg aside enroute to the stage, prompting the actress to retort, "I'm black, too." And Houston reportedly refused to relinquish part of her 45-minute stage time to Stevie Wonder, whose stint was delayed three hours because of stolen equipment. Wonder seemed to recover quickly; it took him seven minutes and two songs—"I Just Called to Say I Love You" and "Dark 'n' Lovely"—to receive the longest ovation of any act. Later, however, he was visibly upset by his truncated performance. "I can't believe this is happening," he said. "This concert was very important to me."

Old, new and odd ensembles were the order of the day. Banned in South Africa since 1979 for donating record proceeds to Amnesty International, Dire Straits dedicated "Brothers in Arms" to Mandela. Eric Clapton, dryly introduced by Straits lead singer-guitarist Mark Knopfler as "the best stand-in we could get," joined the band for "Sultans of Swing, "Walk of Life" and "Romeo and Juliet" before launching into his classic "Wonderful Tonight." By song's end, cigarette lighters flickered throughout the stadium. The Bee Gees joined Bryan Adams for "You Win Again." Chubby Checker twisted with the Fat Boys. Antiapartheid activists, including African National Congress President Oliver Tambo, filled the royal box, customarily reserved for the Windsors. Daryl Hannah joined Steve Van Zandt, Peter Gabriel, Meat Loaf and boyfriend Jackson Browne for a rendition of Van Zandt's "Sun City."

Other standout performers included Tracy Chapman, Al Green, Joe Cocker, Roberta Flack, Natalie Cole, Phil Collins, Hugh Masekela, Miriam Makeba, Nick Ashford and Valerie Simpson, Joan Armatrading and Freddie Jackson. Non-musicians in the show included Denzel Washington, Whoopi Goldberg, Gregory Hines, Philip Michael Thomas and Ali MacGraw, most of whom helped with introductions.

In Britain, Parliament's South Africa supporters tried to stop the BBC's airing of the show, saying that the tribute backed organizations that "maim and kill innocent people in South Africa." But the BBC, the concert's organizers and Oliver Tambo insisted that the money—an estimated $3 million—would be split between the British Antiapartheid Movement and seven other African charities.

Freedomfest closed in marked contrast to the hours of pomp, rock and pageantry that preceded it. Bathed in a simple white light, opera singer Jessye Norman sang "Amazing Grace" with no accompaniment. During her last notes, fireworks lit up the London sky, honoring a man in a jail cell 6,000 miles away. As a silent crowd filed out of the stadium, Stevie Wonder's words still hung in the air. "Nelson Mandela," he had said before leaving the stage, "until you are free, no man, woman or child, whatever color, is really free."

—By Margot Dougherty, with Jonathan Cooper and Janine Di Giovanni in London