What emblem inspired the coiled snake on Metallica's The Black Album cover?

The coiled snake 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.” Metallica adapted that imagery for the lower-right area of its cover, while the band's logo appears diagonally in the upper-left corner.

On the original release, both the logo and snake were embossed so subtly against the black background that they were difficult to see. This restrained design is the main reason the self-titled album became widely known as The Black Album.

The album also includes a song titled “Don't Tread on Me,” connecting the cover imagery with the track list. Later editions made the emblems dark gray and more visible, so modern versions can look slightly different from the first pressing.