The Forrest Gump actor is set to star opposite Emma Thompson in the movie, which chronicles Disney's battle to secure the rights to Mary Poppins.
Author P.L. Travers rebuffed the mogul's efforts to convince her a big screen version of her books would be a good idea.
Rumours suggest it took Disney two decades to be given the green light and he had to surrender script approval rights to the stubborn author.
When filming got underway in the early 1960s, Disney and Travers clashed over song choices, animated sequences and storyline changes.
The difficult working relationship between filmmaker and writer was chronicled in Valerie Lawson's biography Mary Poppins She Wrote, which inspired two documentaries on Travers.
Thompson will play the writer and John Lee Hancock has signed on to direct, according to Variety.
The project is tentatively titled Saving Mr. Banks.