"Riders of the Purple Sage" by Zane Grey
This story is about Lassiter, a gunslinger who is looking for revenge. He shows up in the remote Utah town of Cottonwood. Jane Withersteen is a young and beautiful rancher of the Mormon faith. She is being pressured to marry a church elder, Tulle. The church elders have already run her hired hand, a gentile, off her ranch. Venters is running into trouble with the cattle rustlers that have taken Jane's red herd. He shoots one of their riders, the masked rider, then finds out the rider is a young woman. Vinters finds a hidden valley in the cannon and hides out there and nurses the young woman back to good health. Lassiter and Vinters now must save Jane from the church elders. They have taken everything she cherishes. Lassiter and Jane are on the run from the rustlers and church elders. They go to Vinters hidden valley to hide.
I don't want to tell you anymore as this will ruin the whole story if you haven't read this book. Great classic western, if you haven't read this I recommend you give it a try. A really great book!