Since Shane (1953) is considered a benchmark of Western movies that embodies nearly every theme seen in Westerns since, I feel that some of its characters should be included on the list.
CHARACTER THAT TURNS FROM HIS EVIL WAYS
Quotes from Shane:
Shane: A gun is a tool, Marian; no better or no worse than any other tool: an axe, a shovel or anything. A gun is as good or as bad as the man using it. Remember that.
Shane: You speakin' to me?
Joey: Shane! Come back!