Five official singles promoted Metallica's 1991 album Metallica.
The singles were “Enter Sandman,” “The Unforgiven,” “Nothing Else Matters,” “Wherever I May Roam,” and “Sad but True.” Together, they kept the album prominent across radio, music television, and the band's touring campaign.
The singles were released over an extended period rather than all at once. “Enter Sandman” led the campaign in 1991, while “Nothing Else Matters” and “Sad but True” helped continue the album's visibility into 1992 and 1993.
“Don't Tread on Me” is a common source of confusion. It was issued to rock radio for promotional purposes, but it was not one of the album's commercial single releases. That distinction explains why it is not included in the total.