As Americans reflect on the legacy of Martin Luther King Jnr, an audiotape of an interview with the civil rights leader discovered in a Tennessee attic shed new light on a famous phone call John F. Kennedy made to King's wife more than 50 years ago.
A copy of the original recording was to be played for visitors at the National Civil Rights Museum in Memphis, in the southern US state, at a "King Day" event yesterday.
Historians generally agree that Kennedy's call to Coretta Scott King expressing concern over her husband's arrest in October 1960 - and his brother Robert Kennedy's work behind the scenes to get King released - helped Kennedy win the White House a month later.
King himself, while appreciative, wasn't as quick to credit the Kennedys alone with getting him out of jail, according to a previously unreleased portion of the interview with the civil rights leader days after Kennedy's election.
"The Kennedy family did have some part ... in the release," King says in the recording, which was discovered in 2012. "But I must make it clear that many other forces worked to bring it about also."
King was arrested a few weeks before the election at a sit-in in Atlanta, in the state of Georgia. Charges were dropped, but King was held for allegedly violating probation for an earlier traffic offence and transferred to the Georgia State Prison.
The Kennedys' intervention won the support of black voters, who helped give Kennedy the edge in several key states.
"I think Dr King was aware in the tape that he probably did more for John F. Kennedy than perhaps John F. Kennedy did for him," said Keya Morgan, a New York-based collector and expert on historical artefacts. Morgan acquired the reel-to-reel audiotape from Chattanooga, Tennessee, resident Stephon Tull, who discovered it while cleaning out his father's attic.
Raymond Winbush, director of the Institute for Urban Research at Maryland's Morgan State University, said Kennedy's call to King's wife was political in nature because the Kennedys had been slow to get involved in the civil rights movement.
Winbush said Kennedy did not actually commit to the movement until a few months before his assassination, when civil rights leader Medgar Evers was gunned down by a Klansman in Jackson, Mississippi, just after midnight on June 12, 1963.
The slaying came hours after Kennedy's television speech in support of civil rights and helped propel the struggle for equality to national attention.
"There were a lot of black folks who ... weren't fully committed to his campaign," said Winbush, who is also a historian and psychologist. "That call he made to Coretta moved black folks."
Tull, the Chattanooga man who discovered the tape, said his father had planned to write a book about the racism he encountered growing up in Chattanooga and later as an adult.
Tull said his dad interviewed King when he visited the city, but never completed the book and just stored the recording.
Tull's father is now in his late 80s and under hospice care.