Steven Spielberg said it was tough to persuade British actor Daniel Day-Lewis to play Abraham Lincoln -- but the result was worth the struggle, winning rave reviews and Oscars speculation.
"Lincoln," released in the United States this weekend, is an intimate portrait of the 16th US president as he struggles to change history by abolishing slavery amid the still-raging the Civil War.
The veteran director had wanted to make a film about Lincoln, probably America's most revered president, who was assassinated in April 1865, for more than a decade.
"I've just always had a personal fascination with the myth of Abraham Lincoln," he said ahead of the film's red carpet premier at the American Film Institute (AFI) festival, which traditionally starts the annual Oscars race.
Spielberg lamented that Lincoln has been reduced to "a kind of cultural national stereotype," and no-one has made a film about him since 1939's "Young Mr. Lincoln" by John Ford, in which Henry Fonda played the president.
The three-time Oscar-winning filmmaker decided from the start not to attempt to tell the Republican politician's whole life story, saying: "We would have been dilettantes as filmmakers and as actors.
"We would have just been hitting all the high points and just giving you the headlines, and not giving you any sense of the depth of this character, this man," he told reporters.
With screenwriter and playwright Tony Kushner -- who won a Pulitzer prize for the play "Angels in America" in 1993 -- Spielberg opted to focus on the final months of Lincoln's life and his battle to abolish slavery.
The result is an intimate film mostly shot in interiors, apart from an opening battle scene, where the drama is driven by dialogue and a stellar cast including Tommy Lee Jones, Sally Field and Joseph Gordon-Levitt.
Day-Lewis's performance has already got some talking about the possibility he could win a third best actor Oscar to go with his golden statuettes for 1989's "My Left Foot" and 2008's "There will be blood."
The actor, known for his pickiness in choosing roles, hesitated for a long time to portray a "life that has been mythologized to that extent."
He said he wasn't sure he'd be able to take on the part "in such a way that you can get close enough to properly represent it."
"Least of all did I want to be responsible for irrevocably staining the reputation of the greatest president this country's ever known," he added.
Spielberg confirmed: "It was hard to get him to say yes," adding: "If he had finally and ultimately said no, I would never have made the movie Abraham Lincoln ... It'd be gone."
The director added that he deliberately planned the film's US release -- it comes out in January or February in most other countries -- for after the US presidential elections to prevent it being used by either side politically.
"There's a lot of confusion about the political ideologies of both parties, (which) have switched 180 degrees in 150 years. It's just too confusing, everybody claiming Lincoln as their own," he said.
"I just wanted people to talk about the film, not talk about the election cycle. So I thought it was safer to let people talk about film during the election cycle in this run-up with ads on TV and posters going up and all that.
"But the actual debut of the film should happen after the election's been decided. That was my feeling."