Medgar Evers was shot and killed on 12 June 1963 in Jackson, Mississippi.

On February 18, 1965, in Marion near Selma, a state trooper shot Jimmie Lee Jackson, a young African American man, during a nighttime demonstration. After Jackson died of his wounds just over a week later in Selma, leaders called for a march to the state capital, Montgomery, to bring attention to the injustice of Jackson's death, the ongoing police violence, and the sweeping violations of African Americans' civil rights. Martin Luther King, Jr, leader of the Southern Christian Leadership Conference, scheduled the action for Sunday, March 7. On March 6, George C. Wallace, Alabama's segregationist governor, forbade the march and ordered state troopers to "take whatever means necessary" to prevent it.

Led by Hosea Williams, one of King's lieutenants, and John Lewis, Student Nonviolent Coordinating Committee chairman, some 600 demonstrators walked, two by two, the six blocks to the Edmund Pettus Bridge that crossed the Alabama River and led out of Selma. At the east end of the bridge, the demonstrators encountered a force of sheriff's deputies, deputized "possemen" (some on horseback), and dozens of state troopers. The marchers were told that they had two minutes to disperse. Williams asked to speak with the officer who had given the command. The officer responded that there was nothing to talk about, and moments later he ordered the state troopers to advance. In the tear-gas-shrouded melee that followed, marchers were spat upon, overrun by horses, and attacked with billy clubs and bullwhips. More than 50 marchers, including Lewis, were hospitalized. Drawn from https://www.britannica.com/event/Selma-March