The snake pictured on Metallica’s The Black Album cover was derived from the Gadsden flag.
The Gadsden flag is associated with a coiled rattlesnake and the motto “Don’t Tread on Me.” That motto also appears as the title of a song on Metallica’s album, creating a direct connection between the cover image and the track list.
The original cover used a nearly black design. The Metallica logo and snake were embossed so subtly that they could be difficult to see against the background, which helped inspire the album’s informal nickname, The Black Album.
The image is sometimes misidentified as the Betsy Ross flag or another historic American flag. Those flags have different designs and meanings. The Gadsden flag’s snake and motto are the specific visual references connected with the album artwork.