As the previous educator notes, the setting for The Color Purple is primarily the rural South—Georgia and, later, Tennessee. When Celie discovers the letters that her sister, Nettie, has written to her about her life as a missionary in West Africa, the setting shifts there and Nettie's voice takes over in the novel.
Celie figuratively "escapes" from her miserable life in Georgia with Mr. ___ by reading and writing letters—first, her letters to God, then, the ones that she receives from Nettie. In a way, the true setting of the novel is Celie's imagination. Mr. ____ suppresses the letters from Nettie because he does not want Celie to explore her imagination or any place beyond Mr. ____'s house and farm, where he holds Celie captive.