Revealing mistake: When FDR is getting put in the pool at warm springs for the first time, you can see see his normal legs and they have not been done over by CGI, to look as though he has suffered through polio.
Factual error: The song "I Won't Dance" was not written until the early-'30s, at least six years after the time it was shown being used in the film. However, it is still performed in the dining room scene.
Factual error: In the early scenes of the movie, before Franklin Roosevelt contracts polio, he is seen dancing with his private secretary to a recording by Alice Faye of the song "I'll See You In My Dreams". The song was not written until 1924, more than a year after FDR contracted the disease, and Alice Faye did not record it until 1939.