Backed by June Carter, Carl Perkins, and the Tennessee Three, Cash performed two shows at Folsom State Prison.

[6] A few years after attaining commercial success from songs such as "I Walk the Line", "Understand Your Man", and "Ring of Fire", Cash's popularity waned, in part due to his increasing dependence on drugs.

[7] In 1967, Cash sought help for his escalating drug problems, and by the end of the year, began to get clean and try to turn his career around.

[8] Concurrently, the country portion of Columbia Records underwent major personnel changes, where Frank Jones and Don Law, who had produced several of Cash's albums, were ousted in favor of Bob Johnston, who was known for his erratic behavior and willingness to disagree with studio executives.

They were later accompanied by the Tennessee Three, Carl Perkins, the Statler Brothers, Johnny's father Ray Cash, Reverend Floyd Gressett, pastor of Avenue Community Church in Ventura, California (where Cash often attended services), who counseled inmates at Folsom and helped facilitate the concert, and producer Johnston.

[12] During the rehearsals on January 12, California governor Ronald Reagan, who was at the hotel for an after-dinner speech, visited the band and offered his encouragement.

[14][15] On January 13, the group traveled to Folsom, meeting Los Angeles Times writer Robert Hilburn and Columbia photographer Jim Marshall, who were hired to document the album for the liner notes.

Following "Orange Blossom Special", Cash included a few "slow, ballad-type songs", including "Send a Picture of Mother" and "The Long Black Veil", followed by three novelty songs from his album Everybody Loves a Nut: "Dirty Old Egg-Sucking Dog", "Flushed from the Bathroom of Your Heart", and "Joe Bean".

After a seven-minute version of a song from his Blood, Sweat and Tears album, "The Legend of John Henry's Hammer", Cash took a break and Carter recited a poem.

[30] For The Village Voice, Ann Fisher wrote that "every cut is special in its own way" and Richard Goldstein said the album was "filled with the kind of emotionalism you seldom find in rock".

"[7] Sun Records re-dubbed Cash's previous B-side "Get Rhythm" with applause similar to Folsom's, and it became successful enough to enter the Hot 100.

At San Quentin became Cash's first album to reach number one on the pop chart and produced the number-two hit "A Boy Named Sue".

[40] The album was re-released on October 19, 1999, with three extra tracks excluded from the original LP: "Busted", "Joe Bean", and "The Legend of John Henry's Hammer".

Stephen Thomas Erlewine of AllMusic praised the new version, calling it "the ideal blend of mythmaking and gritty reality.

It includes a DVD produced by Bestor Cram and Michael Streissguth of Northern Light Productions, with pictures and interviews.

Pitchfork Media praised the reissue, saying it had "the force of empathic endeavors, as if [Cash] were doing penance for his notorious bad habits".

[52] Christian Hoard wrote for Rolling Stone that the reissue "makes for an excellent historical document, highlighting Cash's rapport with prison folk".