August 28 · This Day in America
Two hundred and fifty thousand people gather at the Lincoln Memorial, and Martin Luther King Jr. sets down his prepared text. Mahalia Jackson calls out, "Tell them about the dream, Martin." What follows is the country being measured against its own founding sentence, out loud, to its face. He does not reject the promise of 1776 — he demands it be kept. The America the world admires is largely the one that, on its better days, listens to this speech and is ashamed, and changes.
Source: www.archives.gov
Also on this day · 1963
"I have a dream" is not in the speech as written. King had used the refrain before; that day, hearing Mahalia Jackson, he pushed the pages aside and spoke it from memory and nerve. The line America quotes most was, in the moment, unscripted.
Source: www.npr.org