It was written by Billy Strange and Mac Davis specially for Elvis to perform at Elvis' comeback NBC-TV Special, that would air on NBC on December 3, 1968. Later Mac Davis recalled to Billboard: "They had asked for a song about looking back over the years, and oddly enough, I had to write it in one night. I stayed up all night at Billy Strange's house in Los Angeles. He had a little office set up in his garage. I wrote it right there."

Released in the United States in 1969 as a B-side to "Charro!", the title song from the movie Charro!, "Memories" reached number 35 on the Billboard Hot 100 for the week of April 12, 1969.

The song is also included on the album Elvis, the soundtrack album for the NBC TV Special at which it was first performed. For the TV show itself the song was recorded live, but the album features a studio version recorded on June 24.

The book Rock Song Index: The 7500 Most Important Songs for the Rock and Roll Era calls the song "Memories" the "hallmark of [Elvis'] later (fat Elvis) period".

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Wikipedia