On this day 45 years ago, Martin Luther King Jr. delivered his “I Have a Dream” speech during the historic March on Washington. Today Barack Obama, the first African-American to be

nominated for the presidency by either major party, is scheduled to deliver his acceptance speech at the Democratic National Convention in Denver.

WASHINGTON, D.C.—At the climax of his speech, Martin Luther King Jr. raises his arm on the steps of the Lincoln Memorial and calls out for deliverance with the electrifying words of an old Negro spiritual hymn,

“Free at last! Free at last! Thank God Almighty, we are free at last!” 1963

WASHINGTON, D.C—Thousands gather in front of the Washington Monument for the March on Washington, 1963

WASHINGTON, D.C.—Crowds pack the National Mall during the March on Washington, 1963.

WASHINGTON, D.C.—Demonstrators sing in protest in front of the Washington Monument, 1963

WASHINGTON, D.C.—Young men sing during the March on Washington, Aug. 28, 1963.

WASHINGTON, D.C.—Crowds in front of the Washington Monument at the March on Washington for jobs and racial equality, 1963.

WASHINGTON, D.C.—On the steps of the Lincoln Memorial during the March on Washington, Martin Luther King Jr. salutes the flag while standing between Whitney Young Jr. of the Urban

League and Walter Reuther, president of the United Auto Workers union, 1963

WASHINGTON, D.C.—Demonstrators sing "We Shall Overcome" after Martin Luther King's "I Have a Dream" speech, 1963

WASHINGTON, D.C—The March on Washington, 1963.

WASHINGTON, D.C.—The March on Washington, 1963.

WASHINGTON, D.C.—The March on Washington, 1963.

WASHINGTON, D.C.—Rosa Parks during the March on Washington, 1963

WASHINGTON, D.C.—James Baldwin and Marlon Brando at the Lincoln Memorial during the March on Washington demonstration, 1963.

WASHINGTON, D.C.—Bob Dylan and Peter Yarrow (right) during the March on Washington, 1963.

WASHINGTON, D.C.—Harry Belafonte and Burt Lancaster at a protest, 1963

WASHINGTON, D.C.—Sammy Davis Jr. during the March on Washington, 1963

WASHINGTON, D.C.—During the March on Washington, a protester demonstrates in favor of interracial marriage. At the time, many states had laws prohibiting mixed marriages, 1963.

WASHINGTON, D.C.—The March on Washington, 1963

WASHINGTON, D.C.—The March on Washington, 1963.

WASHINGTON, D.C.—A demonstrator during the March on Washington, 1963

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