Last week, Malcolm Burnley was looking for a reference book in a library at Brown University, where he goes to school, when he made a very special discovery. In the university’s dusty archives, he found an audiotape of Malcolm X giving a speech in Providence in 1961.

Fifty years ago, Malcolm X delivered this speech to a mostly white audience of students. He spoke about the legacy of slavery, trying to fight racism and explained how, according to him, Black people should never try to integrate or assimilate into a white society but should instead stay proud and preserve their own identities and culture.

The speech was inspired.

In 1961, Katharine Pierce wrote a paper on the growing Black Muslim movement for her religious studies class. This paper got the attention of Richard Holbrooke, the editor of Brown University’s newspaper, who decided to publish it. (Today, Holbrooke is better known as a U.S diplomat who served in Germany after the country’s reunification. Before he died in 2010, Holbrooke was President Barack Obama’s special adviser on Pakistan and Afghanistan.)

When Pierce’s story ran in the college’s paper, it got a lot of attention, so much so that it reached Malcolm X. Holbrooke and the rest of the staff of the student-run newspaper at Brown then organized for Malcolm X to visit the university. About 800 people witnessed his speech in person in May 1961, but the speech stayed mostly within this community and was eventually forgotten.

Burnley told the Associated Press, “No one had listened to this in 50 years. There aren’t many recordings of him before 1962. And this is a unique speech-it’s not like others he had given before.”