Sixty-four years ago today, on Jan. 1, 1959, Johnny Cash kicked off the new year on a high note: It was on that date that the singer performed at the famous San Quentin State Prison in California, beginning a series of concerts held at various prisons throughout the rest of his career.

Cash, who was arrested several times but never sentenced to prison, performed the concert out of the kindness of his heart and a feeling of compassion for those who had made bad choices as he once had. During his New Year's Day show, Merle Haggard, who was serving time for burglary, was in the audience; in fact, Haggard credits the concert with turning his life around.

"He had the right attitude," Haggard later recalled. "He chewed gum, looked arrogant and flipped the bird to the guards — he did everything the prisoners wanted to do. He was a mean mother from the South who was there because he loved us. When he walked away, everyone in that place had become a Johnny Cash fan.”

Cash went on to perform at several other prisons, ultimately inspiring two albums: Johnny Cash at Folsom Prison, released in 1968, and Johnny Cash at San Quentin, released in 1969. Johnny Cash at Folsom Prison includes a live version of the song "Folsom Prison Blues" -- originally from Cash's debut album, With His Hot and Blue Guitar -- which became a No. 1 hit for Cash. Johnny Cash at San Quentin includes two versions of Cash's song "San Quentin," along with "Folsom Prison Blues" and "A Boy Named Sue," the latter of which became Cash's only Top 10 single on the Billboard Hot 100 chart.

The Man in Black did more than just perform at prisons, always for free, though: He tirelessly campaigned for the rights of prisoners. Cash became an outspoken advocate for those behind prison walls.

"He always identified with the underdog," says Cash's younger brother, Tommy Cash. "He identified with the prisoners because many of them had served their sentences and had been rehabilitated in some cases but were still kept there the rest of their lives. He felt a great empathy with those people."

Johnny Cash at San Quentin is available for streaming and purchase on Amazon.

This story was originally written by Gayle Thompson, and revised by Angela Stefano and Annie Zaleski.

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