What is Belle Watling's purpose in Gone With the Wind?
Belle Watling is the owner of a brothel that Rhett visits upon occasion. She provides evidence of one of the aspects of Rhett's life away from Scarlett and Tara that infuriates Scarlett at times and makes him all the more attractive, because he's hard to get, at other times. As Scarlett said,
Let me see that handkerchief. R. B. And she's driving away in Rhett Butler's carriage! Oh, if I just wasn't a lady what wouldn't I tell that varmint!
There are rumors that Belle and Rhett have an illegitimate son. Rhett definitely is a friend of Belle's. After the raid on the former slaves who attacked Scarlett, Rhett and Belle cooperate to shield Ashley and other members of the Ku Klux Klan who are at risk of arrest. Afterwards, Melanie attempted to thank Belle.
"How can I thank you enough for what you did for us? How can any of us thank you enough?" Belle: "I got your note saying you was going to call on me and thank me. Why, Miss Wilkes, you must have lost your mind....It wouldn't be fitting at all." Melanie: "It wouldn't be fitting to thank a kind woman who saved my husband's life?" Belle: "Miss Watkins, there ain't never been a lady in town nice to me like you was...And I got to thinking about you being left a widow with a little boy if Mr. Wilkes got hung and he's a nice little boy, your boy is, Miss Wilkes. I got a boy myself..."
The character of Belle Watling serves an important function in the story. For one thing, she epitomizes the enormous social upheaval caused by the Civil War, so much so that the distinction between respectable and not-so-respectable women has become blurred. Scarlett O'Hara deeply resents Belle, not least because she sees many similarities between them in terms of character and temperament. Scarlett wants to feel superior to Belle, but has the honesty to admit that she has no right to. After all, her behavior towards Rhett is hardly what one would consider appropriate for a fine, upstanding Southern lady.
Belle's character acts as a kind of moral lesson for Scarlett, reminding her that she has a position in society, a reputation to protect, irrespective of the turmoil of conflict. Scarlett is a very willful, headstrong woman, but at the same time, she needs to be aware of the dangers of straying too far from the path of social convention, for that way lies potential ruin. To this end, Belle Watling provides a useful, salutary warning.