Aging and emerging activists are flocking to “The Black Power Mixtape,” and the very title of this documentary about the halcyon days of the struggle with commentary from contemporary rappers and musicians encapsulates its appeal.

There are many astonishing things about this one hour and 40 minutes of American history from 1967 to 1975, not the least of which that it comes from archival footage shot by Swedish filmmakers hoping to provide a portrait of the country during this dramatic period.

“For years I had heard about the footage but didn’t believe it,” said Goran Olsson, the director, last week after a screening at the IFC Theater in New York City. “I stumbled on it while working on another project.”

What Olsson discovered was a trove of footage of the Black Panther Party, even while some of its members were exiled in Algiers; a defiant interview of Angela Davis at the time of her trial; and, most rewarding, the enthralling charisma of the late Stokely Carmichael (Kwame Ture).

“This was during the time Stokely was with the Student Nonviolent Coordinating Committee, just before his days with the Panthers,” said Bill Johnson, who was a member of the Panthers during this period. “Seeing the film brought back a lot of memories, like seeing our old headquarters on Seventh Avenue and the children we fed. That was 40 years ago.”

With this month being the 40th anniversary of the prison revolt at Attica in upstate New York, the director felt it might be useful to include footage of the uprising. “I’m only sorry I didn’t include footage of Shirley Chisholm’s presidential campaign,” Olsson said.

He needn’t apologize for not including everything, since there is so much significant footage that even American filmmakers and documentarians have failed to capture.

To witness Carmichael at press conferences, roaming the world and even interviewing his mother, Mable, is worth the price of the ticket.

Olsson praised the participation of producer Danny Glover. “He was so important in providing the context for all the footage,” he said.

Glover, fresh from Paris with plans to return shortly, hurried from one theater to another, participating in question and answer sessions at the IFC Center and the Lincoln Center Cinemas.

“I am very proud to be part of this project, which I believe will help renew the discussion about the importance of Black power,” Glover said, visibly exhausted from participating in the sessions and introducing the film at each screening. “And this is particularly true for the present generation, who need to know more about the organizations and individuals, many of whom sacrificed their lives in the struggle for civil and human rights.”

This point is poignantly emphasized in the film by Davis, as she answers a question about the nature of violence. “I grew up on Dynamite Hill in Birmingham, Ala., a place we called ‘Bombingham’ because there were so many bombings of our homes and churches,” she said.

It is riveting testimony such as this that conveys the power of the documentary. That power is epitomized in Carmichael’s interview with his mother, which is evidence of how and where he gathered his first lessons in revolutionary commitment.

That commitment reaches well beyond the ’60s and ’70s and into the current generation, as far away as Sweden, to touch filmmakers such Olsson and his colleagues. “It is something I felt I had to do,” he said.

When asked why there were no images in the film of Talib Kweli, Erykah Badu and the other present-day figures who provided commentaries, Olsson said, “It was our sense that to see them would have been a distraction. The footage is so compelling that there was no need to see them-just to hear them was enough.”

At the very beginning of the film, we hear Abiodun Oyewole, a member of the Last Poets, state that America is lucky that African-Americans have not risen up and demonstrated their total outrage against racism and white supremacy.

It is an outrage that simmers between each segment of “The Black Power Mixtape.” As Johnson noted, “It’s a good outside perspective-now we need it from the inside out.”