Macho Callahan is a 1970 Mexican-American Western film directed by Bernard L. Kowalski and starring David Janssen, Jean Seberg, Lee J. Cobb and James Booth.

[1] The screenplay concerns a Union soldier who is imprisoned in a Confederate prison camp during the American Civil War.

Placed behind bars during the war, Diego Callahan, also known as "Macho," travels to Texas looking for the man responsible for his imprisonment.

He quarrels with a one-armed Confederate Army colonel, David Mountford, over a bottle of champagne and kills him in front of his wife, Alexandra.

Now in love with the man who has killed her husband, she travels with Callahan and his partner, but Wheeler's posse is in pursuit.