Setting and character are significant to "A Rose for Emily" because they interact to create external and internal conflict in the story. The setting itself functions as the primary antagonist in the story. The mysterious "We" that tells the narrative begins by stating, "Our whole town went to her funeral..." This shows that the town (the setting) and the narrator are one. The "We" that speaks is the voice of the town, and as the opening line of the story demonstrates, they have taken a great interest in Miss Emily.
Throughout the story, the town antagonizes Emily by gossiping about her and interfering with her personal life. It could be argued that the town's interference with Emily's love life leads her character to a mental breakdown, and the desperate act of killing Homer Barron.
For instance, early on in the story, the narrator gossips that Emily was "thirty and still single" because she her father had "driven away" all the young men interested in her. The Grierson family, which was considered aristocracy in the antebellum South, apparently "held themselves a little too high for what they really were." The town wants readers to know that Emily was not allowed to marry because her father felt that no interested young man was of equal family lineage. This detail shows just one tradition of the time and place in which Emily lived.
Miss Emily was born in the Civil War Era, and much of the story takes place post Civil War, and while certain aspects of the town were changing, customs regarding dating and marriage had not much altered. Fathers and/or elders in a family still had the final say on who young women within the family unit married, and women were expected to marry within their socioeconomic class. Even though "the town" says they do not agree that Emily is not "above" others due to her family lineage, they contradict this assertion by interfering in her love life. In particular, the townspeople interfere by gossiping about Emily dating a Northerner: "Of course a Grierson would not think seriously of a Northerner, a day laborer...Poor Emily, Her Kinsfolk should come to her." The townspeople come to the conclusion that Emily has greatly transgressed social custom, and they choose to interfere. First, they send a Baptist minister to her house to talk to her about her unconventional (or sinful) approach to courting. When this is unsuccessful, the minister's wife sends a note to Emily's cousins in Alabama, explaining the situation.
As these details illustrate, the setting has created the expectation that Emily will marry a Southerner, likely someone of her own social standing, after first receiving the approval of her family. Most importantly, though, she should certainly not be intimate with a man outside of marriage. If she is gallivanting around town with this Northerner, the townspeople seem to have reasoned, she had better get hitched. This expectation creates the primary external conflict in the story, and it also informs Miss Emily's internal conflict.
In an interview on "A Rose for Emily," William Faulkner explained Miss Emily's motives when he said,
The conflict was in Miss Emily, that she knew that you do not murder people. She had been trained that you do not take a lover. You marry, you don't take a lover. She had broken all the laws of her tradition, her background, and she had finally broken the law of God too, which says you do not take a human life. And she knew she was doing wrong, and that's why her own life was wrecked. Instead of murdering one lover, and then to go and take another and when she had used him up to murder him, she was expiating her crime.
In other words, Ms. Emily was impacted by the gossip and interference of the town. She felt guilty for being with a man outside of marriage and for transgressing societal traditions as well as her own background. What would her father say, if he knew she had stooped low enough to date a laborer from the North, and he had refused her? The setting, manifested as an antagonist, functioned to make her feel guilty enough to kill Homer Barron and pushed her to a kind of mental breakdown, which is why she kept Homer's body. First, she killed him because he refused to marry her; second, she kept his body to atone for her sins. She would be respectable and marry Homer, dead or alive.