The scenes where James Stewart wanders around in amazement at the Washington monuments were "stolen", since the US Parks Service had denied the studio permission to film near them.
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 30 days prior to the ban.
Bitterly denounced by Washington insiders angry at its allegations of corruption, yet banned by fascist states in Europe who were afraid it showed that democracy works.
According to the New York Times, "the Boy Scouts of America objected to having any part in Mr. Capra's reform movement," and Frank Capra therefore had to use the fictitious name of the Boy Rangers.
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Joseph P. Kennedy saying that he felt the film would damage "America's prestige in Europe" and should therefore be withdrawn from European distribution.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.