Final answer:
William Faulkner was a postman while writing 'As I Lay Dying,' a novel set in the fictional Yoknapatawpha County.
Step-by-step explanation:
William Faulkner's occupation while he wrote As I Lay Dying was that of a postman. Faulkner, one of America's renowned novelists known for his stream of consciousness writing and contributions to the Southern Literary Renaissance, authored As I Lay Dying in 1930. This period follows his great discovery of the fictional possibilities within his home state of Mississippi, which led him to create the setting of Yoknapatawpha County used in many of his works, including this novel.