The Rev. Martin Luther King Jr. is notably one of the most prominent faces of the civil rights movement. He is best known for his famous "I Have a Dream" speech. But there is one speech he delivered that was not discovered until 2014, and it was right here in Arizona.

King gave a speech titled "Religious Witness for Human Dignity" at Arizona State University on June 3, 1964. This was just days before the Senate passed the Civil Rights Act on June 19.

In his speech, King mentioned the filibuster taking place that was keeping the bill from being passed. "The bill must pass and it must pass soon if our nation is to maintain its health," he said.

There was no record of this speech until 2014, when a Phoenix woman found some old tapes donated by local civil rights leader Lincoln Ragsdale Sr. One of those tapes had a recording of the aforementioned speech. That speech recording is now available for public consumption through the ASU Library. You can listen to the speech and read a transcript here.

You also can learn more about Arizona's history surrounding MLK Day in a story by KTAR.