The Sound and the Fury, like the majority of Faulkner's works, revolves around the societal reaction to the death of the Old South.
The Old South refers to a pre-civil war, slave owening, patriarchal culture of the southern states. The culture of the South was built around slavery and a strong caste system, and when slavery was abolished the residents of the South didn't know how to psychologically adjust to this new world.
Jason Compson is the character that most directly exhibits this sense of disorientation and anger that characterized this time period. His sister, Caddy, had a child out of wedlock and then left him to raise a headstrong baby girl. Jason's anger at his niece is a direct reflection of many of the feelings those who thrived under the culture of the Old Sough felt once their way of life was destroyed. Specifically, Jason was angry over her assertion of personal rights, her revolt against his patriarchy, and finally her choice to go out into the world on her own. All of these actions can be seen as a direct symbol of the ways that the New South felt the Old South had violated their world view.