Kevin Costner wants you to know that his new film, the first part of “Horizon: An American Saga,” is not three hours long.

“It’s two hours and fifty-one minutes,” he told CNN in a recent interview as he sipped on a soothing cup of tea with honey during a busy press tour. “Let’s be really clear about that.”

If anyone knows the film’s running time down to the second, it would be Costner. He co-wrote, produced, directed and co-stars in the epic western set around the time of the American Civil War. Costner said he’s been trying to get the film made for decades and has no concerns that the length might be a turnoff to those with short attention spans.

“I make movies for people so that they won’t be bored,” he said. “I give them a taste of something in a different direction, which is probably why it’s hard for me to get them made at first ‘cause they’re a little different.”

From any perspective, it’s an ambitious project.

There are four planned films with the first “chapter” being released on June 28 and the second in theaters on August 16. The first film sets the scene of a clash between a group of settlers and the indigenous people who already live in the west.

Costner is currently filming the third movie.

“These stories and these people, their lives keep evolving and their situations get even more desperate, more thrilling, more is at stake,” he said. “And because we know them and we care about them, and the third one I’m filming right now is incredibly dynamic.”

Fans of Costner’s 1990 film “Dances with Wolves” and his role in “Yellowstone” are aware of his affinity for westerns, something Costner attributes to the inherent “drama” of these settings.

“If we can just close our eyes and go back, realize how hard it was because you were going west, but you were also coming up against people who had lived there for thousands of years and didn’t want to let go of it,” he said. “And so you had no law out there. There was nothing to really protect you. The only thing that was taking you out there was this appetite in America that if you were strong enough and bold enough, you could hold onto something if you were willing to actually defend.”

“That kind of attitude is a recipe for disaster and nothing but clash. And how do you deal with someone who wants what you have? If you do that in a real simple way, it’s boring,” Costner added. “But if you do that in a way that you realize the dilemma, that must be what people were going through back then, it can be really very entertaining.”

The mix of history and a star-studded cast was heady for Costner, who directs several heavy hitters, including Abbey Lee, Sienna Miller, Sam Worthington, Jena Malone, Luke Wilson and more. It’s the kind of film he’s long wanted to see and make.

So with all the work directing entails, why did Costner also decide to take on the role of cowboy Hayes Ellison in the film? It was personal, he said.

“I felt like I was the guy to play this guy,” Costner said. “You know, I named my son after him, who’s in the movie [Hayes Costner, 15, makes his acting debut in ‘Horizon’] and it’s just been a journey for me, too. I just believe in the power of movies.”

And while he’s no historian, Costner recognizes the importance of releasing films set pre- and-post-Civil War at a time when America feels divided. He’s hopeful that his project will spark audiences to reflect on how the states came to be united in the first place.

“What has to occur in any culture in life is a level of empathy, a level of understanding history, really understanding,” he said. “And you can have empathy when you understand history. It’s like we are in this together and we can flourish. If we don’t, we will be divided.”