The narrator frequently tells us just what we should think about a character. We get our narrator’s opinion through extensive use of foils – consider aristocratic Alfred to Augustine’s democratic idealism. Or Eva’s saintliness contrasting with Topsy’s devilry. Alternatively, the narrator comes out and just informs us what sort of a person a given character is – take Marie St. Clare, whose behavior is clearly self-absorbed and destructive. The narrator specializes in cutting asides on Marie – we particularly like the line, "Marie always had a head-ache on hand for any conversation that did not exactly suit her" (386). It’s not hard to tell that this is an unsympathetic character.
Stowe frequently makes use of the North/South divide in the United States to explain characters. Miss Ophelia, for example, is a "typical" northerner: she is hard working, harsh yet virtuous, opinionated, and democratic. She is an abolitionist yet prejudiced against blacks. Augustine St. Clare, on the other hand, is a "typical" southerner: wealthy, lazy, and educated. He has too much time on his hands, drinks too much alcohol, and is generally indulgent of his slaves because he recognizes they make his life easier. Simon Legree, alternatively, was raised in the North and has many of the northern character traits. It turns out that those character traits allow him to be ultra harsh in his treatment of his slaves.
Evangeline, or "Eva," turns out to be a regular little evangelist. Her name is simply the manifestation of an interior reality. Through her love and compassion, she transforms Topsy from a hardened little sinner into a pliable young girl. She helps her father "see the light" and St. Clare decides to be a better man and do the right thing because of her. She shows Miss Ophelia what it really means to love people and be a Christian and Miss Ophelia repents of her own prejudice against black people because of it. So her name and her nature are one.
In addition, her last name, St. Clare is a reference to St. Clare of Assisi, a 12th century saint who exhibited her virtues from a young age. Like Eva, St. Clare proved to be a light to all around her, despite being young.
Ironically, Evangeline’s nickname, "Eva" means "living one." On a symbolic level, however, this meaning is important. Although Eva dies, her example lives on in the hearts and minds of all the people she touched. In Christianity, the concept of triumphing over death has enormous power. Christ is the eternal living one. Like Christ, Eva eternally lives on because of the influence she had over people like Miss Ophelia, Topsy, and Tom.
Mr. Shelby and Mr. Haley are introduced immediately in terms of their social status. Mr. Shelby is a gentleman, while Mr. Haley, though perhaps wealthy, is clearly not. In fact, the narrator refers to Shelby as "Mr. Shelby" and Haley as "Haley" without the honorific. We are clearly intended to think more highly of "Mr. Shelby" than of "Haley," despite the fact that neither man is completely honorable.