She sang for JFK and planned to sing for Obama's inauguration. There are many articles about her online. Here are excerpts from one of them.
Odetta's repertoire of 19th-century slave songs and spirituals inspired several generations of singers including Bob Dylan, Joan Baez, Janis Joplin and Tracy Chapman. Her classically trained voice could sweep from husky low notes to delicate high tones and it became the soundtrack of the struggle to end racial discrimination, inspiring freedom marchers in Alabama and Mississippi and protesters in Washington.
"The first thing that turned me on to folk-singing was Odetta," Bob Dylan said in a 1978 Playboy interview. He had heard something "vital and personal" he said, adding: "I learned all the songs on that record, Odetta Sings Ballads and Blues."
Odetta's finest hour was her singing at the August 1963 march on Washington, a turning-point for the civil rights movement when she sang "O Freedom", a song dating to the days of slavery. She said blues and spirituals drew her into the civil rights movement, like two rivers running together. The words and music captured "the fury and frustration that I had growing up".