It is only too appropriate that America’s greatest documentary filmmaker has taken on America’s greatest athlete.

From the house he has lived in for the last 40 years, Ken Burns has worked on a documentary about the life of Muhammad Ali.

The four-part, eight-hour documentary “Muhammad Ali” will premiere on PBS on Sept. 19. Combine Ken Burns and Muhammad Ali and you have the product that you expect.

“When we started this project back in 2014 he was alive and we knew we could not get him, that he would not be able to do an interview,” Burns said in a recent phone conversation.

Ali famously fought Parkinson’s disease for decades, and remained a public figure who simply could not do interviews. He died in June of 2016 at the age of 74.

Rather than talk to the man himself, Burns relies on scores of archival footage, new interviews, and his use of actor Keith David as the primary narrator is perfect.

“We talked two of [Ali’s] four wives. His two daughters. His brother,” Burns said. “A lot of his family and friends, people in his corner, and hangers on.”

In a recent 25-minute conversation, we covered Ali and why Burns remains loyal to his genre, and PBS.

Mac Engel: What prompted you to take on a subject that is already so well-reported, chronicled and documented like Ali?

Ken Burns: It is a hard one, but they are all hard. We chose him because he is irresistible as a subject. His life intersects with so many themes of the 20th century; sports, the role of sports in society. Of race, war, faith, religion, politics. You name it he’s there, and he happens to be the greatest athlete of the 20th century.

Your point is well taken in that this is a subject unlike most of the subjects we have undertaken in which it is really well-documented.

What we felt is there had not been anything comprehensive. It was our intention to take his whole story, from birth to death by Parkinson’s and dying as the most-beloved person on the planet.

ME: Did you have any personal experience with Ali, not necessarily meeting him, but something that made an indelible impression?

KB: I did meet him. But I remember I was 7 years old in the summer of ’60, and my dad telling me there was this dramatic fight and this guy named Cassius Marcellus Clay, which as Jim McKay noted sounded like a Roman name.

Four years later we were having to “deal with” two Black men fighting; one who is young and brash and bragging, and the other who is the representation of brute force in Sonny Liston.

There was a lot of thought that one of them [Ali] was not behaving the way an athlete should, and the subtext was “a Black athlete” should behave. We noticed that in the way Howard Cosell talked about him.

And we loved it when Ali won.

We ended up on a college campus, and opposed from the very beginning the war in Vietnam. And [Ali’s] stance just cemented his hero-dom in my book.

In the mid ’90s, I was raising money in Los Angeles. I was in a coffee shop at around 11 in the morning, and the breakfast crowd was gone. I was waiting at the counter, and I turn around and there is Muhammad Ali.

And we had this wordless conversation together.

I said, Oh my goodness, you’re Muhammad Ali. He said, I am. I said, I love you. He said, I love you, too.

I said, I won’t bother you. He said, You’re not bothering me.

I got my tea and walked out. By then Parkinson’s had really taken over, but even in that he sparkled with a life that I had never seen before.

ME: When you started doing documentaries the genre was small, so what inspired you to do this as your life’s work?

KB: My dad was a cultural anthropologist and an amateur still photographer. He built a darkroom in our house, and my earliest memories of him are developing stuff.

I had wanted to be a feature filmmaker from the time I was 12, shortly after my mom died. Because I had seen my dad cry for the very first time, not at her illness or her death, but at a movie.

I realized it provided an emotional self haven for him. I wanted to do film.

I went to Hampshire College in fall of ’71, and it was the second year of its existence. And it totally re-arranged me; all of the teachers of film were social documentary still photographers.

They reminded me that what is and what was is as dramatic as the human imagination makes up. When I got out of college, I had accidentally merged this new love with an old love I didn’t realize I had, which is history.

The last time I took an American history class was the 11th grade, when they make you take it. I didn’t know how much I love history.

I’m just a storyteller, I’m not a historian.

ME: When you started in the ’70s, a documentary was a niche and now the genre has exploded ...

KB: Yeah, it’s great. Early on, I was trying to use narrative techniques that a documentary didn’t have to be homework. It could be sharing a story.

The same laws of storytelling apply to me as to anyone in Hollywood, it’s just that we can’t make stuff up.

What we have seen in the subsequent decades is that this golden age of documentaries is getting bigger and bigger.

People are beginning to realize how tired some of those [fiction] plot forms are, and how interesting studying Nexium might be, or Michael Jordan, or Anthony Bourdain.

Those are marginal to the fact that people like Werner Herzog, who is a great feature filmmaker, has been doing documentaries for the last 20 or 30 years.

There are lots of opportunities going on, and I have just stayed in my little corner at PBS. I have lived in rural New Hampshire for the last 42 years, and made all of the films here.

ME: Have you made any film and thought, “I wish I could do that one again,” or when it’s done you have a contract with yourself that it’s over, and that’s it?

KB: It’s a painting. It’s a composition. You put in who you are at the time. Sometimes you get new information after the fact.

After my 1997 film on Thomas Jefferson came, a few years afterwards DNA evidence conclusively proved that the Hemings family, the descendant of his slave Sally Hemings, were a 99.9 match with him.

Now, the film still worked, but I didn’t know this when we were making it.

ME: You have a brand that if you create something, it’s not just good but great. Like Steven Spielberg, there is this assumption that if it’s Ken Burns, it’s amazing. Does it ever work against you?

KB: I know what you are saying, and I am flattered you’d say it. I stayed in public television, but I could have saved myself all of that fundraising work and just go to a premium cable service.

I could get the $30 million, which I needed to do the Vietnam series. That was just pulling teeth to get that through fundraising.

But if I got that $30 million (from a subscription service) they would not give me the 10 1/2 years I needed to make it. And PBS allowed me that. I could do it right.

It’s four years later since that came out, and that is really satisfying for me. The “brand” has never been in the way.

I think there are some archives who think because it’s a Ken Burns film we can charge more, but we are still PBS, so help us out.

ME: You ever thought about trying fiction, either a feature length or a short?

KB: I have periodically been involved, and there is some interest in that world for a film I made on Jack Johnson. That may happen.

I like my day job.

You’re so flattering to put me in the same brand category as Steven Spielberg, but I sat on stage with him and interviewed him. Over the course of the evening we realized we obey the same laws of storytelling.

He can make stuff up, and I can’t. But that’s OK.

I love what I do. If I’m given 1,000 years to live I won’t run out of topics on American history.

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