Mourning Is Red — Charles R. Pike

There was only one fight that Jubal Cade was looking for, and that was with the man who murdered his wife. Meantime, he was a doctor; he didn’t want to kill. But when he found Gill Last, he found more than a man with his guts shot all over the trail to Blazeville. He found a feud of mean treachery and brutal death. And he wasn’t going to walk away from there until plenty more warm blood had flowed into the cold and merciless earth.