Metallica's 1991 album Metallica reached number one on its first Billboard 200 chart appearance.
It became Metallica's first album to top the U.S. album chart. The record opened with approximately 598,000 copies sold in its first week and remained at number one for four consecutive weeks. Its chart performance helped demonstrate that a heavy metal album could achieve unusually broad mainstream reach.
The success was not limited to the United States. Metallica debuted at number one in ten countries, including the United Kingdom, Australia, Canada, Germany, and New Zealand. In America, it continued to chart for hundreds of weeks, an exceptional run for a metal album.
The result is sometimes described imprecisely as the album's “debut at number one” without distinguishing the chart from the single charts. The Billboard 200 is the U.S. album chart; “Enter Sandman,” by contrast, had its own Hot 100 peak at number 16.