The narrative refers to "three Yoknapatawpha's original settlers" but only gives one of them - Alexander Holston - a name (421). In other Yoknapatawpha fictions this group always includes Samuel Habersham, sometimes along with his (unnamed) son; in "Hand Upon the Waters," the group includes an ancestor of Gavin Stevens as one of the three.
Thinking about the books in his home, Charles Mallison the ones "his grandfather had . . . heired in his turn from his father" (149). With this reference the story seems to want to establish the pedigree of the family Charles belongs to: his mother's maiden name is Stevens, one of the oldest names in the story of Yoknapatawpha. (In the earlier novel Light in August, Gavin Stevens refers to his father's father as a man who owned slaves in Yoknapatawpha before the Civil War.)
This is the "barefoot" field hand who is driving the carriage the first time Gavin Stevens sees the woman he will marry after he himself has returned from World War I (245).
When Charles Mallison passes through Jefferson at the start of World War II, he has a kind of prevision of a young man from Yoknapatawpha whose death during the fighting overseas will be reported in the local paper, along with a photograph showing "the country-boy face" inside "the uniform still showing the creases of the quartermaster shelves" (251).
When Charles Mallison passes through Jefferson at the start of World War II, he has a kind of prevision of the local young men who will soon be killed in the fighting, and the grief of "those who had created" them, without realizing that the day would come when their child "might die in agony" in a foreign place they "had never even heard of before" and didn't even know how to pronounce (251).
When Charles Mallison passes through Jefferson at the start of World War II, he thinks how soon newspapers delivered by the "RFD carrier" report the news of the local young men who have been killed in the fighting (251). The federal "R[ural] F[ree] D[elivery]" system brought mail directly to Americans who lived in the countryside, away from post offices.
Rafe McCallum acquired the horse that Max Harriss buys from "some owner" who may have "ruined" it by trying "to break its spirit by fear or violence"; it is rumored that McCallum acquired the horse "because its owner wanted to destroy it" (210-11).