“Now, there ain't no sense in going around being mad. You clear your head so you can think sensibly. Then I want you to think real hard on whether or not Lillian Jean's worth taking a stand about, but keep in mind that Lillian Jean probably won't be the last white person to treat you this way." He turned toward me so that he looked me full in the face, and the seriousness of his eyes startled me. He held my chin up with the wide flat of his hard hand. "This here's an important decision, Cassie, very important—I want you to understand that—but I think you can handle it.”
What does the excerpt show about the historical time period of the story?