“Enter Sandman” was the first song written for Metallica’s 1991 album, according to the album’s recording history.
The song’s music emerged early in the writing process, while its lyrics were completed later than the musical ideas. That unusual sequence is part of the track’s documented development: the lead single was the first composition written but the last to receive its lyrics.
The songwriting credits are shared by Kirk Hammett, James Hetfield, and Lars Ulrich for the music, with Hetfield credited as lyricist. The final song centers on nightmares and childhood fears, themes that helped distinguish it from a conventional love song or straightforward heavy-metal anthem.
Its early creation did not mean the song was immediately finished. Metallica continued revising material during the album’s demanding sessions at One on One Recording Studios. The completed track ultimately became both the album opener and its lead single, giving it an unusually important role in the record’s history.