Three outlaws rob the stage and then flee. When their horses give out they murder some Indians to get fresh ones. But this puts the Indians on the war path and they have to take refuge in an Army fort to avoid them. The Indians then arrive offering peace if the three men are turned over to them. The fort's commanding Officer wants peace but the rules say the men must be tried in a white man's court leaving the Indians no choice but to attack.
A trio of masked bandits rob a stagecoach secretly assisted by one of the passengers. The fleeing bandits come across some unarmed Navajo who they shoot and steal their horses. One of the Navajo survives and informs the tribe who sets his tribe on the warpath against all whites. The commander of the US Cavalry fort who is friendly with the Navajo chief is caught in the middle.
The film was made in 1950 and was originally to have been released through Eagle-Lion but was picked up for release by RKO.
Originally the film was shot with Howard Da Silva in the lead. After he was accused of Communist leanings, RKO ordered DaSilvas scenes reshot with Brian Donlevy.
Like High Noon, Slaughter Trail has continuing ballads throughout the film that ask and answer questions as well as narrate the story. It may be debated whether the film was made "straight," or was satiric, due to the even then well known Western set pieces such as a stagecoach holdup, Indian attacks, and the army standing between hostile Indians and townspeople being commented on by songs that often break the fourth wall. The writer of the film Sid Kuller was a well known comedy writer and also wrote some of the films songs. One of the films songs I Wish I Was became a hit song of the year.