This is the young black man in "Barn Burning" whom Abner Snopes sends to Mr. Harris to tell him that "wood and hay kin burn" (4) - Ab's barely disguised way of threatening to burn Harris' barn. This messenger never appears directly. In his testimony against Ab, Harris calls him a "strange nigger" (4), a term that in the context of the story and the South at that time means he is a black person whom Harris has never seen before.
The narrator of Light in August identifies the black man who rides to the Sheriff's house in Jefferson "on a saddleless mule" to report Christmas' violent disruption of the "revival meeting" at "the negro church" only as "the messenger" (322, 323). He is anxious to convince the Sheriff that the blacks had not been "bothering" Christmas beforehand (324).
This is the "inscrutable" man in Light in August - "either a grown imbecile or a hulking youth" (435) - who takes Lucas Burch's note to the sheriff. A bit later, this man points Byron Bunch toward Burch.
This is the Negro in Light in August whom Sheriff Kennedy forces to talk about the situation at the Burden place. At first the man pleads ignorance but then, after being whipped by the deputy, says "It's two white man" who have been living there (293). He tells the Sheriff that he doesn't live nearby, but "down the road" (292).
This is the man in Flags in the Dust who provides Byron Snopes with the Ford car in which he flees Yokapatawpha after robbing the bank. He is identified simply as "the negro [Byron] sought," and Byron finds him just off the Square, on a "street occupied by negro stores and barber shops" (272).
Neither the Negro man whom Boon shoots in "Lion" and again in Go Down, Moses nor the cause of the quarrel between the men is explained. In "Lion" Quentin describes the man in terms that, like the entire episode, will make a 21st century sensibility wince: "They said he was a bad nigger, but I don't know" (189). When the scene was revised for the novel, the third-person narrator calls him a "negro" instead (223). In both texts this man is armed with "a dollar-and-a-half mail order pistol" that misfires (189, 223).
The mammy who takes care of Narcissa and Bayard's new-born son at the end of Flags in the Dust is referred to only as "the placid, gaily turbaned mountain who superintended his hours" (395).