On several occasions in 1965, marchers in Selma, Alabama had attempted to march across the Edmund Pettus Bridge to Montgomery in protest of discriminatory voter registration practices. At one march, Alabama state troopers with billy clubs, tear gas, and bullwhips attacked 600 marchers. At the last march, the Alabama National Guard was ordered by a federal judge to protect 3,200 marchers as they crossed the Edmund Pettus Bridge.

