The following script is from "Lincoln" which aired on Feb. 10, 2013. Lesley Stahl is the correspondent. Ruth Streeter, producer.
With the 150th anniversary of the Civil War, we're going through another Abraham Lincoln revival. Not that interest in him ever really fades: there've been close to 16,000 books written about him and now, Steven Spielberg's movie "Lincoln" which has been nominated for 12 Academy Awards.
The film is filled with things about our 16th president that we -- who aren't Lincoln scholars -- didn't know. It's Daniel Day-Lewis, whose been nominated for an Oscar for best actor, who brings the great man to life.
[Lincoln: I can't listen to this anymore. I can't accomplish a goddamn thing of any human meaning or worth until we cure ourselves of slavery and end this pestilential war.]
Daniel Day-Lewis: I never, ever felt that depth of love for another human being that I never met. And that's I think probably the effect that Lincoln has on most people that take the time to discover him.
After agreeing to take the part, Daniel Day-Lewis spent a year reading and doing research into Lincoln the man.
Daniel Day-Lewis: He does feel as if he's carved in stone, when you first approach him, because of the way he was as a man. As you begin to discover him, it's almost as if he welcomes you in.
[Lincoln: Tell us the news from the Hill.
Ashley: Ah, well the news...
Lincoln: Why for instance is this thus, and what is the reason for this thusness.]
So much about Daniel Day-Lewis' portrait rings true to the man including things most of us didn't know: like what Lincoln sounded like.
Daniel Day-Lewis: There are numerous references to him having a high-pitched voice.
Lesley Stahl: Did that influence you?
Daniel Day-Lewis: It's a clue, I suppose. All clues are potentially helpful.
[Lincoln: And come February the first, I intend to sign the Thirteenth Amendment.]
Doris Kearns Goodwin: That's definitely the way people who heard him speak at the time said he spoke. So somehow he mastered that voice.
Even Lincoln historians, like Doris Kearns Goodwin, who was a consultant on the movie, say the portrait -- down to the high voice -- was eerily authentic because of Daniel Day-Lewis' method acting.
Doris Kearns Goodwin: Steven told me later that he never came out of that voice until after the filming was over.
Lesley Stahl: So the whole time they were filming he stayed in character - which is his method?
Doris Kearns Goodwin: Absolutely.
"Steven" is Steven Spielberg the director, who decided that the movie would be only about the last four months of Lincoln's life when -- worried that the Emancipation Proclamation would be voided after the war -- he pushes for passage of the 13th Amendment to end slavery once and for all.