On July 20, 1968, Johnny Cash hit No. 1 on the country charts with the live version of "Folsom Prison Blues." The song is the first track on his hit At Folsom Prison album.

This ascent to No. 1 was actually the second time "Folsom Prison Blues" had charted: Back in 1955, the studio take on the tune — which appears on Cash's debut album, With His Hot and Blue Guitar — hit No. 4 on the country radio airplay chart.

The re-do of "Folsom Prison Blues" was recorded at Folsom State Prison in California on Jan. 13, 1968. Cash played two sets — occasionally alongside wife June Carter Cash — after Carl Perkins and the Statler Brothers performed. According to a Rolling Stone Country oral history of At Folsom Prison, the appearance was both a way to nudge Cash to release some music and a reflection of his empathy.

"John had a real feeling for the down and out, for the prisoners. For anybody like that," said bassist Marshall Grant. "He came from very humble beginnings in Arkansas. So even though he acquired a lot of things in life, he still felt for these people and he made it very obvious, too. He was so real with it.

"And that’s what brought him to prisons," Grant added. "And a lot of them turned their lives around because of our willingness to go entertain them that told them that we cared."

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For the performance, Cash enlisted familiar collaborators: Grant, guitarist Luther Perkins and drummer WS "Fluke" Holland. (Guitarist Al Casey also performed on the song.) The audience was instructed to cheer wildly after Cash uttered his traditional opening line — "Hello, I'm Johnny Cash" — which set a raucous tone for the performance.

"When Luther Perkins kicked off "Folsom Prison Blues" ... of course, they’d heard "Folsom" before and they knew Luther was going to kick it off," Grant recalled in the Rolling Stone Country piece. "But when he started doing it loud and clear, everybody turns toward Luther. We all did on the stage and so did they, and they thought that he was the greatest thing that ever picked up a guitar, which in my opinion, he was. But he knocked those people for a loop and that just added flame to the fire from the introduction."

The At Folsom Prison version of "Folsom Prison Blues" does have extra oomph thanks to crowd noise — a mix of authentic responses and cheers added after the fact — although the musicality of the live take also helped. Cash and the band are fired up to be performing, and clearly keyed up to give the audience a good time.

"Folsom Prison Blues" spent four weeks atop the country charts, and crossed over to peak at No. 32 on the pop charts on the way to landing Cash his first Grammys trophy, for Best Male Country Vocal Performance. At Folsom Prison also hit No. 1 on the country charts and is certified triple platinum.

"After that album was released and become a hit, it quadrupled the amount of people that knew about Johnny Cash," Holland told Rolling Stone Country. "And then came the San Quentin album. I think that’s the two things that skyrocketed him to stardom.

"Then the thing that put the icing on the cake, as we call it, in the late '60s and early '70s, was when we did the weekly ABC network show [The Johnny Cash Show], and of course that just finished it up," he continued. "I don’t know if that could have happened, though, if the prison shows hadn’t happened before that. That set Johnny Cash up."

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