The first three discs feature outtakes and alternate versions of songs recorded for American Recordings, American II: Unchained, American III: Solitary Man and American IV: The Man Comes Around. The fourth disc, My Mother's Hymn Book, features gospel songs Cash first learned from his mother as a child and was later reissued as a standalone album in 2004. The final disc is a best-of distillation of the first four American albums.
"I'm Going to Memphis" was previously recorded by Cash for his 1960 album Ride This Train.
"Waiting for the Train" was previously recorded by Cash for his 1963 album Blood, Sweat & Tears.
"No Earthly Good' was previously recorded by Cash for his 1976 album The Rambler.
"The Fourth Man in the Fire" was previously recorded by Cash for his 1969 album The Holy Land.
"Dark as a Dungeon" was previously recorded by Cash as the B-side to his 1964 single "Understand Your Man".
"I'm Moving On" was previously recorded by Cash in 1984 as a duet with Waylon Jennings. This version would not be released until 2014 on Out Among the Stars.
Rock historian Graeme Thomson in his monograph, The Resurrection of Johnny Cash: Hurt, Redemption, and American Recordings has called Unearthed a monolithic achievement.[3]
Note: All tracks previously unreleased. A different take of "Down There by the Train" was issued on the 1994 album American Recordings. "Flesh and Blood" is a newer version of the original that was written for I Walk the Line (Soundtrack).
Note: All tracks previously unreleased. A solo version of "Like a Soldier", a version of "Drive On" featuring different lyrics, and an acoustic studio version of "Bird on a Wire" were issued on the 1994 album American Recordings.
Note: All tracks previously unreleased, except "Wichita Lineman" and "Big Iron" which were previously released on the original vinyl pressing of American IV: The Man Comes Around. The final version of "The Man Comes Around" was also released on American IV: The Man Comes Around.
My Mother's Hymn Book is a collection of Christian spiritual songs and hymns that Cash originally learned from his mother while growing up. The album features only Cash's voice and a single acoustic guitar. This disc was released as a stand-alone disc the following year (his 89th overall album) under the same title, and peaked at #9 on the Christian music album chart. In the album's liner notes Cash mentions that this is his favorite album he ever made.
Tracks 6, 9 and 10 were previously recorded for Hymns from the Heart (1962); tracks 5, 11, 14 and 15 were previously recorded for Sings Precious Memories (1975); and track 7 was recorded in concert for The Survivors Live (1982). Several other songs, such as track 13, had been performed by Cash on TV or live in concert, but formal studio recordings had not yet been issued until now.
Although the images used on the standalone CD depict Cash near the end of his life, most of the recordings on My Mother's Hymn Book actually date to Cash's early sessions for American in 1993–1994 (hence the fact they only feature Cash performing by himself).