Nearly everyone knows about Martin Luther King, Jr.'s famous "I Have a Dream" speech, but museum archivists recently unearthed a powerful speech by the civil-rights leader that history nearly forgot.
The once-lost audio reveals a speech that King delivered to commemorate the 100th anniversary of Abraham Lincoln’s Preliminary Emancipation Proclamation in 1962. The New York State Museum rediscovered the speech on reel-to-reel magnetic tape, and uploaded it to YouTube Monday as part of an online exhibition about the event.
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Officials with the New York State Education Department, which operates the museum, said its copy is the only known recording of King's speech.
"This is a remarkable treasure," Merryl Tisch, chancellor of the state Board of Regents, said in a statement. "More than 50 years later, Dr. King's voice has come back to life."

Martin Luther King, Jr. delivering his address to the New York State Civil War Centennial Commission at the Park Sheraton Hotel in New York City on September 12, 1962.
Image: New York State Education Department
In the speech, King said two American documents, the Emancipation Proclamation and the Declaration of Independence, have been invaluable contributions to civilization.
"All tyrants, past, present and future, are powerless to bury the truths in these declarations, no matter how extensive their legions, how vast their power and how malignant their evil," he said.
Although King had a prior engagement, he accepted Gov. Nelson A. Rockefeller's invitation to speak at the New York State Civil War Centennial Commission held at the Park Sheraton Hotel on Sept. 12, 1962.
Enoch Squires, a research associate for the commission, recorded the speech. King's speech was one of about 400 reel-to-reel audio recordings that Squires’ widow donated to the museum in 1979.
Listen to King's full speech in the YouTube video, above. If you'd like to read along, the text of the speech is embedded, below. For more information about the recording, including images of the typewritten speech that King read, visit the New York State Museum's online exhibit.
Martin Luther King Jr.'s Emancipation Proclamation Speech

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