In the movie, in the bedroom where they are quartered in Roosevelt's home, the King and Queen are distressed to see a collection of framed antique political cartoons depicting conflict between England and the US. The Queen speculates the cartoon are intended as a veiled insult. In fact, those antique/historic cartoons are located in the foyer of Roosevelt's home, King George viewed them them upon arriving in the foyer, and made a brief humorous remark to Roosevelt about the cartoons.
On June 11, 1939, the New York Times printed the menus for all of the meals served to the British royals during their visit to Hyde Park. As depicted in this movie, the picnic menu was as follows: Hot dogs, if weather permits. Beer and soft drinks. Cold ham from various States. Turkey, smoked and plain. Various salads. Baked Beans and brown bread. Doughnuts and ginger bread cookies. Coffee.