Final answer:
Essie and others understood Samuel O'Quinn's murder as a result of racial violence and racism prevalent during the civil rights movement.
Step-by-step explanation:
Essie and the other black people in Centreville understood that Samuel O'Quinn was murdered because of racial violence and racism prevalent in society.
Racial violence was a significant issue in the Southern United States during the civil rights movement. Incidents like the murder of Emmett Till and the attacks on black families in Detroit and Beaumont exemplify the violent response of white racists to challenges to the social order.
These incidents and others like them highlighted the deep-seated racism and discrimination that black people experienced, leading to a growing civil rights movement and calls for equality and justice.