Kevin Costner doesn't think of 'Horizon: An American Saga' as a passion project.

The 69-year-old star has directed and financed the Western film series – the first of which failed to impress audiences and critics when it was released last month – but dislikes the term that many have used to describe the pictures.

Kevin told AARP: "Calling it that actually minimises it.

"I've been passionate about a lot of things that I've done. This is a good thing about America. People came west. It's part of our legacy. I just believed in it so much that I put my money into it, but I've had that belief about everything in my life."

The first 'Horizon' movie included precise historical information and Kevin used books to improve his knowledge about the time period.

The 'Tin Cup' actor said: "I just read books. I'm thrilled by details and the survival instinct that people displayed on the frontier. I love the spontaneity and the mindset of engineers in the era.

"Movie viewers are usually rushing towards the gunfight. But somebody had to plot these towns out. Somebody had to go out there with a shovel. Wheels broke down.

"And the way pioneers solved many problems elegantly, just ingeniously, I always like reading about that. And then I think, 'Can I fashion a story, a dialogue, around those facts?'"

The second 'Horizon' movie was pulled from its August release date due to the poor response to the opening flick but Kevin says he will judge the success of the film based on its long-term appeal.

He said: "Movies aren't just about opening weekend. Ten years later, a good movie will still be shared. Success is: Will you revisit it and show your daughter, show your son? Will you revisit it because you wonder about it, because you find new details? Those are the measures."