After award-winning composer Leonard Rosenman recorded a score for the film, which he personally didn't care for but was given freedom to be experimentally creative, the score was rejected. While Jerry Goldsmith is credited with "Music" on the film's credits, the credit is misleading as he composed no original score for the film, instead it was tracked with cues from four other westerns he scored: 100 Rifles (1969); Rio Conchos (1964); Morituri (1965) and Stagecoach (1966) . Which is why he did not receive a credit like "Original Music composed & Conducted by".
One of this 20th Century Fox film's main movie poster taglines was "one of them is going to die hard!". The Fox studio would later have a successful "Die Hard" action movie franchise with that phrase appearing in each installment's title.
Charlton Heston's last name rhymes with Western. Four years after this 1976 film, Heston would co-star in 1980's The Mountain Men (1980), a western with a similar title to The Last Hard Men (1976), with both movie titles featuring the words "The . . . Men".