How is the Old South represented in Faulkner's "A Rose for Emily"?

The character of Emily Grierson is used by Faulkner to symbolize the Old South and its decline. She is a living monument of a romanticized past—based on a rigid social hierarchy and its associated code of chivalry. This explains why the townsfolk hold Emily in such high esteem. In a defeated, postbellum South, the Grierson name acts as a nostalgic reminder of the so-called glory days before the Civil War. The people of Jefferson want to hang on to the memory of yesteryear for as long as they possibly can, and so Emily gets a pass for her eccentricity and evident disdain for her social inferiors.
In "A Rose for Emily," Faulkner holds up a mirror to the society of the Old South. In its reflection we see a society that is stuck in the past, unable to move on, unwilling to acknowledge that the world outside Jefferson has changed forever. Although slavery may have been abolished, the old social hierarchies remain. And they corrupt the town's public life. Everyone can smell the revolting stench emanating from the Grierson residence, but instead of launching a proper investigation, the authorities merely send out some men to go and neutralize the smell. The old ways continue to exert such a hold on the minds of the townsfolk that their values are warped, and they become complicit in immoral acts. So long as Emily lives, and the Grierson name continues to exude its strange, bewitching magic, such moral corruption will live on.