On March 20, 1965, President Lyndon B. Johnson notifies Alabama’s Governor George Wallace that he will use federal authority to call up the Alabama National Guard in order to supervise a planned civil rights march from Selma to Montgomery.

Intimidation and discrimination had earlier prevented Selma’s Black population—over half the city—from registering and voting.

On Sunday, March 7, 1965, a group of 600 demonstrators marched on the capital city of Montgomery to protest this disenfranchisement and the earlier killing of a Black man, Jimmie Lee Jackson, by a state trooper.

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