Led by guitarist Pops Staples, the Staple Singers--which also featured four of his offspring--forged a revolutionary blend of R&B and gospel. They started recording in the 1950s, but it was in the turbulent '60s that they began to incorporate social messages into their songs and make their way to the forefront of the soul music scene. The Staples crossed numerous boundaries; their "This May Be the Last Time" was adapted by the Rolling Stones as "The Last Time," and they made a stirring appearance in the Band's cinematic swan song THE LAST WALTZ. The group was fittingly inducted into the Rock & Roll Hall of Fame in '99.