Hanks described to Colbert on Wednesday how actors would ride the same horse across Western films and how he learned about the horse Stewart would ride while visiting the Hollywood legend's house during a photoshoot for Life magazine.
"So he's showing me around his living room, his parlor, and there is no sign of Jimmy Stewart the movie star anywhere in this thing," Hanks said about Stewart.
Hanks said he discovered a painting of a horse hanging up in Stewart's house and asked him about it.
"That was my horse Pie and I rode that horse in all my Westerns. The wranglers would keep it out by Griffith Park. That's where we all had our horses," Hanks said, recounting what Stewart told him while giving his best impersonation of the Hollywood legend.
Stewart told Hanks that Henry Fonda made the painting of Pie as a gift, however, Pie died just a week after.
News of the World is coming to theaters on Christmas Day. Hanks is also set to portray Elvis Presley's manager Colonel Tom Parker in biopic Elvis. Austin Butler stars as the music icon.
Hanks was bald for the interview, stating that he had to wear multiple wigs for Elvis.
"Let me put it this way, Elvis is as big as he ever has been and much of that credit goes to the guy I played in this movie," Hanks said about Parker.