On the steps of the Lincoln Memorial in Washington, D.C., the African American civil rights movement reaches its high-water mark when Martin Luther King Jr. delivers his "I Have a Dream" speech to about 250,000 people attending the March on Washington for Jobs and Freedom. The demonstrators—Black and white, poor and rich—came together in the nation’s capital to demand voting rights and equal opportunity for African Americans and to appeal for an end to racial segregation and discrimination.

The peaceful rally was the largest assembly for a redress of grievances that the capital had ever seen, and King was the last speaker. With the statue of Abraham Lincoln—the Great Emancipator—towering behind him, King used the rhetorical talents he had developed as a Baptist preacher to show how, as he put it, the “Negro is still not free.” He told of the struggle ahead, stressing the importance of continued action and nonviolent protest. Coming to the end of his prepared text (which, like other speakers that day, he had limited to seven minutes), he was overwhelmed by the moment and launched into an improvised sermon.

He told the hushed crowd, “Go back to Mississippi, go back to Alabama, go back to South Carolina, go back to Georgia, go back to Louisiana, go back to the slums and ghettoes of our northern cities, knowing that somehow this situation can and will be changed. Let us not wallow in the valley of despair.” Continuing, he began the refrain that made the speech one of the best known in U.S. history, second only to Lincoln’s 1863 “Gettysburg Address”:

“I have a dream,” he boomed over the crowd stretching from the Lincoln Memorial to the Washington Monument, “that one day this nation will rise up and live out the true meaning of its creed: ‘We hold these truths to be self-evident: that all men are created equal.’ I have a dream that one day on the red hills of Georgia the sons of former slaves and the sons of former slaveowners will be able to sit down together at the table of brotherhood. I have a dream that one day even the state of Mississippi, a state sweltering with the heat of injustice, sweltering with the heat of oppression, will be transformed into an oasis of freedom and justice. I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character. I have a dream today.”

King had used the “I have a dream” theme before, in a handful of stump speeches, but never with the force and effectiveness of that hot August day in Washington. He equated the civil rights movement with the highest and noblest ideals of the American tradition, allowing many to see for the first time the importance and urgency of racial equality. He ended his stirring, 16-minute speech with his vision of the fruit of racial harmony:

“When we allow freedom ring, when we let it ring from every village and every hamlet, from every state and every city, we will be able to speed up that day when all of God’s children, Black men and white men, Jews and Gentiles, Protestants and Catholics, will be able to join hands and sing in the words of the old Negro spiritual, ‘Free at last! Free at last! Thank God Almighty, we are free at last!'”

In the year after the March on Washington, the civil rights movement achieved two of its greatest successes: the ratification of the 24th Amendment to the Constitution, which abolished the poll tax and thus a barrier to poor African American voters in the South; and the passage of the Civil Rights Act of 1964, which prohibited racial discrimination in employment and education and outlawed racial segregation in public facilities. In October 1964, Martin Luther King Jr., was awarded the Nobel Peace Prize. On April 4, 1968, he was shot to death while standing on a motel balcony in Memphis, Tennessee—he was 39 years old. The gunman was escaped convict James Earl Ray.