In 1942, when a ban on American films was imposed in German-occupied France, the title theaters chose Mr. Smith Goes to Washington (1939) for their last movie before the ban went into effect. One Paris theater reportedly screened the film nonstop for thirty days prior to the ban.
To make his voice hoarse for the filibuster scene, James Stewart dried out his throat with bicarbonate of soda. However, both Frank Capra and Stewart revealed in interviews that his throat was periodically swabbed with mercuric chloride.
Jean Arthur did not get along with James Stewart during filming, possibly because she had wanted her Mr. Deeds Goes to Town (1936) co-star Gary Cooper to be cast as Mr Smith. Arthur thought Stewart was being deliberately a bit too cute for his own good and that Cooper was more masculine and had a stronger screen presence.
James Stewart knew this was the role of a lifetime, one that could place him near the top of the Hollywood heap. Jean Arthur later remembered his mood at the time: "He was so serious when he was working on that picture, he used to get up at five o'clock in the morning and drive himself to the studio. He was so terrified something was going to happen to him, he wouldn't go faster."
One reason Frank Capra made this film was to help him get over the loss of his infant son, who had died following complications from a tonsillectomy. Initially Capra wanted to make a film about Frédéric Chopin, but Columbia head Harry Cohn nixed that on the grounds that it would be too expensive. Capra and Cohn were constantly at loggerheads over budgets, despite Capra being Columbia's most successful director with - at the time - two Oscars under his belt.
The Washington press corps were highly indignant at the way they were portrayed in the film. Consequently a great deal of the initial reviews from the capitol were very negative. One of their chief objections was that the film made them all out to be drinking too much.
The set for the Senate chamber was constructed on two newly built adjoining stages at Columbia, stage 8 and 9. The set was built almost to scale, and was at that time, the largest set built on a Columbia sound stage.
The film was banned in Nazi Germany, Fascist Italy, Soviet Russia and Falangist Spain. According to Frank Capra, the film was also dubbed in certain European countries to alter the message of the film so it conformed with official ideology.
The screenplay was originally purchased by Columbia as a vehicle for Ralph Bellamy, with Harold Wilson slated to produce. Once Frank Capra became the director, the project, planned as a sequel to Mr. Deeds Goes to Town (1936), was entitled "Mr. Deeds Goes to Washington", and was to star Gary Cooper, reprising his role as Longfellow Deeds. Cooper was unavailable for the role, however, and James Stewart was borrowed from MGM. "I knew he would make a hell of a Mr. Smith," Capra said. "He looked like the country kid, the idealist. It was very close to him."
The film's premiere was sponsored by the National Press Club in Washington, DC, at Constitution Hall with over 4,000 in attendance, including congressmen, Supreme Court Justices and Cabinet members. Frank Capra was seated next to Montana Sen. Burton Wheeler, who was one of many public officials who disliked the negative representation of Washingtonian politics, and left the theater midway through in a huff. Capra described the aftermath as "the worst shellacking of my professional life."
Frank Capra and his crew went to Washington, DC, to film background material and to study the Senate chamber, which was replicated, full scale, in precise detail on the Columbia lot. James D. Preston, who was Capra's technical advisor for the Senate set and political protocol, was a former superintendent of the Senate press gallery.
In his autobiography, Frank Capra states that after the film's general release, he and Harry Cohn received a cablegram from U.S. Ambassador to Great Britain Joseph P. Kennedy saying that he felt the film would damage "America's prestige in Europe" and should therefore be withdrawn from European distribution. In response, they mailed favorable reviews of the film to Kennedy which persuaded him not pursue the matter any further, even though he still maintained his doubts.
In 1941 Columbia was sued by Louis Ullman and Norman Houston, both of whom claimed that this film was plagiarized from their respective written works. Screenwriter Lewis R. Foster testified that he wrote the story specifically for Gary Cooper, and director Frank Capra testified that he had seen only the synopsis of Foster's story and had intended to use it as a sequel to Mr. Deeds Goes to Town (1936). Columbia won the case.
Information in the MPAA/PCA Collection at the AMPAS Library indicates that in January 1938, both Paramount and MGM submitted copies of Lewis R. Foster's story to the PCA for approval. Responding to a Paramount official, PCA Director Joseph Breen cautioned, "We would urge most earnestly that you take serious counsel before embarking on the production of any motion picture based on this story. It looks to us like one that might well be loaded with dynamite, both for the motion picture industry and for the country at large." Breen especially objected to "the generally unflattering portrayal of our system of government, which might well lead to such a picture being considered, both here and more particularly abroad, as a covert attack on the democratic form of government." Breen warned Columbia that the picture needed to emphasize that "the Senate is made up of a group of fine, upstanding citizens, who labor long and tirelessly for the best interests of the nation," as opposed to "Senator Joseph Paine" and his cohorts. After the script had been rewritten, Breen wrote a letter to Will H. Hays in which he stated, "It is a grand yarn that will do a great deal of good for all those who see it and, in my judgment, it is particularly fortunate that this kind of story is to be made at this time. Out of all Senator Jeff's difficulties there has been evolved the importance of a democracy and there is splendidly emphasized the rich and glorious heritage which is ours and which comes when you have a government 'of the people, by the people, and for the people.'"
Edmund Mortimer was first chosen for the role of Senator Agnew, and studio records/casting call lists reflected this. However, Mortimer dropped out of the finished film entirely, and the role went to H.B. Warner.
The trivia items below may give away important plot points.
Originally, the ending was much, much longer. It included scenes such as Mr. Smith going back to his home state and given a parade (with Saunders); the Taylor machine being crushed; Smith on a motorcycle and stopping to see Senator Paine; forgiving him and everyone going to see Smith's mother. It was cut after a preview audience's response. Some of the footage can be seen in the theatrical trailer.
During Smith's filibuster, he mostly sticks to improvisation and reading from historical documents (The Declaration of Independence, The Constitution, etc). However, during one scene (immediately following the montage of the dueling newspapers), he reads from the King James Bible, specifically the "love passage" in 1 Corinthians 13.