In the film planning stage, the director Sergio insisted on asking Henry Fonda to play the role of Joe the Lonely Gunner, but the film's production company could not pay the film's remuneration for Henry Fonda, who was already well-known in Hollywood at the time, and Sergio had to give up. His second candidate was Charles Bronson, who had starred in business cards such as "The Great Escape" and "The Heroic Seven Dragons", but Bronson refused Sergio's invitation after reading the script. Next, Ty Harding, Steve Reeves, and James Cobain all rejected the role. Then Sergio approached Richard Harrison, and as a result, he refused his invitation after learning about Sergio.
The desperate producer brought a list of the second-tier actors who were not well-known in Hollywood. The producer asked Harrison to recommend candidates. Harrison pointed casually and pointed on Clint Eastwood's name. Clint Eastwood was an unknown little actor at the time, so the crew followed Harrison's "instructions" and found Eastwood.
Director Sergio León did not want Ennio Morricone to be the soundtrack for the film at first, because although the two were classmates in childhood, Morricone’s past works did not leave him any deep impression. impression. After hearing Morricone's original composition for the film, Leon quickly put other people's works aside. Since then, all the soundtracks of Leon's films have come from Morricone. In the soundtrack of the film, the character's individual music is Morricone's golden signature. He composed his own music for the three main characters in the film. The whistle and whiplash used by him also appeared in the soundtrack for the first time.
