To heighten the tension of Spencer Tracy's final summation to the jury, the scene was filmed in a single take.
Stanley Kramer was advised against casting Fredric March and Spencer Tracy in the lead roles as it was felt young audiences would not want to see veteran stars.
Fredric March and Florence Eldridge, the actors who play Matthew and Sarah Brady, were married in real life from 1927 until his death in 1975.
Was the first in-flight movie ever shown on Trans World Airlines.
The real-life John Thomas Scopes, upon whom the Bertram Cates character was based, had an unusual epilogue of his own. After the famous trial, he was approached by a representative of the University of Chicago, which offered him a scholarship for graduate study in geology. Scopes then did geological field work in Venezuela for Gulf Oil of South America, and went on to make a name for himself in the field of geology.