The set still stands outside Tucson Arizona and is an active studio and Old West theme park called Old Tucson. Since it was built in 1939, Old Tucson has served as the set for many famous Westerns such as Rio Bravo (1959) and Tombstone (1993). Little House on the Prairie (1974) also used the studios.
In 1940, when this film was released, Jean Arthur was forty years old and her "love Interest", William Holden was only twenty-two.
Chief Fighting Bear, who served as technical advisor on the film, was head of the Black River Apaches.
The starring role was written with Gary Cooper in mind, and although he had previously co-starred twice with Jean Arthur (including The Plainsman (1936)) he declined the role that was ultimately inherited by William Holden.
New York Times notes that Wesley Ruggles began to build his sets in the fall of 1939, but the war halted production until 1940. A news item in Hollywood Reporter, however, notes that Ruggles canceled production on the film in September 1939 when Columbia threatened to slash the budget.
According to publicity materials, some 140 buildings representing Old Tucson were constructed on location and 1,000 locals were hired as extras. Some came from families who had settled the area, so they were essentially portraying their own ancestors.
At the time of this film, the need for 40 year old year Jean Arthur, still claiming to be 35, to be photographed from the left side, particularly in her close-ups, was never more apparent.