Martin Luther King, Jr., was the eloquent voice of the modern civil rights movement. More than any other individual, he articulated the aspirations and grievances of African Americans who sought the rights promised by the U.S. Constitution. King pioneered the use of civil disobedience against racial segregation and discrimination. His powerful oratory invoked religious and patriotic imagery in support of full civil rights for all Americans. He inspired thousands of sympathizers to join his nonviolent crusade and persuaded untold millions of the justice of his cause.