King wrote the iconic speech from his hotel room the night before, finishing the draft well after midnight. He pulled from events in American history and the power of historical documents to draw straight lines between promises made and broken to the American people. King’s adviser, Wyatt Walker, urged him not to use the “dream” rhetoric he had used in the past, which Walker called trite and cliché. The theme was not included in King’s prepared remarks, but the following day, as he neared the end of delivering the speech, gospel singer Mahalia Jackson shouted to King “Tell them about the dream, Martin.” In response, King shifted away from his script, and instead spoke from the heart about his dream, creating one of the most defining moments in American history.
The speech was given as part of March on Washington for Jobs and Freedom. While the event happened in 1963, it was originally to have taken place in 1941.