International commemorations will be held at London's Trafalgar Square, as well as in the nations of Japan, Switzerland, Nepal and Liberia. London Mayor Boris Johnson has said King's speech resonates around the world and continues to inspire people as one of the great pieces of oratory.
On Aug. 28, 1963, as King was ending his speech, he quoted from the patriotic song, "My Country 'tis of Thee" and urged his audience to "let freedom ring."
"When we allow freedom to ring when we let it ring from every city 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, great God almighty, we are free at last,'' King said.
The civil rights leader was assassinated five years later.
The Rev. Bernice King opened the celebration Wednesday at an interfaith service. King said that her father is often remembered as a freedom fighter for equal rights and human rights, but he was most importantly a man of faith.
Obama considers the 1963 march part of his generation's "formative memory." A half-century after the march, he said, is a good time to reflect on how far the country has come and how far it still has to go, particularly after the recent acquittal of George Zimmerman in the fatal shooting of Trayvon Martin, an unarmed black teenager.
Race isn't a subject Obama likes to talk about in public, but the Martin case is one time he has done so.
In an interview Tuesday on Tom Joyner's radio show, Obama said he imagines that King "would be amazed in many ways about the progress that we've made." He listed advances such as equal rights before the law, an accessible judicial system, thousands of African-American elected officials, African-American CEOs and the doors that the civil rights movement opened for Latinos, women and gays.
"I think he would say it was a glorious thing," he said.
But Obama noted that King's speech was also about jobs and justice.
- AP