NEW YORK (AP) — At 84, Harry Belafonte doesn’t sing publicly anymore. But today, his music is no less rich or compelling than before, even delivered in the form of the spoken words he voices lyrically and from his heart.

“What a blessing, what a blessing,” he marvels in his distinctive sandy whisper, summing up his life in a recent interview.

Of course, Belafonte has not been the only beneficiary of that busy, blessed life. He has brought pleasure to millions with his singing (earning the first-ever gold record for his 1956 album Calypso, which produced the inescapable smash single Banana Boat (Day-O). Moreover, he gained international stardom in concert, on TV and film in such movies as Carmen Jones (1954), The World, the Flesh and the Devil and Buck and the Preacher. He won a Tony Award in 1954 for his featured role in John Murray Anderson’s Almanac.

And he blended his artistry with activism, playing a key role in the civil rights movement alongside such leaders as the Reverend Martin Luther King Jr as well as then-Attorney General Robert Kennedy (whom he pushed for more aggressive protection of blacks) and President John F Kennedy (whom Belafonte schooled as a presidential candidate on the importance of King’s mission, while simultaneously advising King on how to work with the Kennedys).

The child of a Jamaican-born domestic worker in Harlem, Belafonte understood and condemned social injustices from a young age, and resolved to help correct them.

“I wasn’t an artiste who turned activist, I was an activist who turned artiste,” he explains.

Belafonte’s journey forms a connect-the-dots map of six decades of popular culture and social crusades. And it drives Sing Your Song, a beautifully conceived documentary about Belafonte’s life and the era the rest of us have shared with him. It premieres tomorrow night on HBO.

At first, he felt narcissistic and superfluous doing a documentary, says Belafonte, hosting a reporter at his awards and mementos-filled office in the Manhattan neighbourhood once known as Hell’s Kitchen.

“What have I got to say that people want to hear, if they’re not hearing it during the time I lived doing it?” he reasons. But then he learnt a lesson from Marlon Brando, his old friend with whom he took acting classes in the early 1950s and subsequently became allied in the civil rights movement.

When Brando died in 2004: “I felt not only that America had lost a great artiste, but a great social force,” Belafonte says. “But people knew little about his social activism, and he passed away without leaving any record of it.

“So I started going around, identifying all of the people who were my peers who had done incredible things but never talked about it. What began as a simple exercise in providing for the archives wound up taking four years of nothing but filming all over the world.”

He had hundreds of hours of film with no idea what to do with it. Then filmmaker Susanne Rostock entered the picture.

Together, they crafted this footage (plus abundant other historical film and photos) into a saga gracefully narrated by Belafonte that spans the distance from a 1950s Las Vegas engagement, where he defiantly swam in his hotel’s whites-only swimming pool to organising a celebratory concert (with such stars as Tony Bennett, Sammy Davis Jr and Peter Paul and Mary) after a triumphant Selma, Alabama, civil rights march in 1965 to masterminding 1985’s all-star We Are the World recording that earned millions for African famine relief to coordinating Nelson Mandela’s first visit to the US, after being released from prison in 1990 — with many other milestones along the way.

Says Miriam Makeba, the late Grammy-winning South African singer and civil rights activist, in the film: “Belafonte means a lot to people, struggling people around the world, because he took all our struggles and made them his own.”

But making the film didn’t satisfy Belafonte.

“I could touch on everything, but I couldn’t go in-depth into many things,” he says. “That’s when a book appeared as a possibility.”

That memoir, Harry Belafonte: My Song, written with Michael Shnayerson, was released last week by Knopf.

It was only by accident that Belafonte ever rose to such prominence. Returning to New York after serving in World War II, he was working as a janitor’s assistant when, as gratuity for an apartment repair job, he was given a ticket to a production at the American Negro Theatre in Harlem.

“It was an epiphany,” he says, his eyes lighting up at the memory, “the people and stories and lights and magic.”

Deliriously happy just to be working behind the scenes, he eventually got cast in a performing role: as a troubadour to link the scenes of a production of John Steinbeck’s Of Mice and Men.

He had never sung before, and even then didn’t see himself as a singer: “I was acting,” he says. But this acting role introduced him to folk, blues and calypso music, with their power to convey important stories. He set about to tap these music genres for a singing act.

It wasn’t long before he was a household name, a mainstream star, a matinee idol recognised around the world.

More than a half-century later, he remains a handsome, princely presence, though clearly comfortable enough to poke fun at himself: When he learned that Sing Your Song would premiere at the 2011 Sundance Film Festival, “I understood what that meant: big time!

And I hadn’t been big time,” he laughs, “in a long time.”

And even now, he is candid in acknowledging the questions that persist for him, questions underlined for him in making this film.

“A lot of things about myself newly mystified me,” he says. “Forget that you did it, forget that you were there, forget that all this bumped into your life. Why you?”

He is still sorting out why him and what his life’s work means.

“Each time we achieved something,” he muses, “I woke up the next day and I said, ‘We got it! We did it!’ But we didn’t get it: Here we go again.”

Fittingly, his film ends not with a declaration, but with him posing a question, and a call to arms for fellow activists: “What do you do now?”