God Is My Colt.

A gang of landgrabbers, led by Mexican bandit Manuel, terrorizes the small town of Landford City. The sheriff asks the army for help, which orders Captain Mike Jackson to see what is going on in his old home town and also search for a government agent who has disappeared in that area. Jackson immediately finds himself in the middle of fistfights and shoot-outs with the bandits, who not only have a tight grip on the local farmers but also force Mary, the woman Jackson once intended to marry, to work as a saloon girl.