There are other hints, too, in Section I. For example, the mayor, Colonel Sartoris, "fathered the edict that no Negro woman should appear on the streets without an apron (288), and also a reference to the graves of Union and Confederate soldiers.
Additionally, all of Miss Emily's servants are "Negro," and in the North, servants were less likely to be so. The prevalence of African-American servants in the South was largely a function of the aftermath of the Civil War and the freeing of slaves, who seldom had the financial wherewithal to leave the areas in which they had been slaves. Many former slaves stayed with the plantations on which they had been enslaved, continuing to be field workers or house servants.
The first hints as to the story's Southern setting are the references to the cotton gins and cotton wagons. These are followed by allusions to the cemetery where the bodies of Union and Confederate soldiers were buried following the battle of Jefferson, which suggests that the setting of the story has a Civil War history. Another hint of the story's Southern setting is the information that "Colonel Sartoris" issued an order "that no Negro woman should appear on the streets without an apron." It was a Southern custom to continue to refer to former Confederate officers by the title of their military rank, and the Colonel's "edict" suggests the post-Civil war culture of the South. Finally, Miss Emily's having a "man servant" named Tobe also points to a Southern setting. All of these details make Faulkner's description Emily's old and decaying home, once grand, especially meaningful.
I'd also like to point out that the house Emily Grierson lived in was a typically southern style house. Even though it was decaying, the description that is being given matches the huge estates once owned by plantation owners