Metallica formed in 1981. Details:

• The band was founded by James Hetfield (vocals/guitar) and Lars Ulrich (drums) in Los Angeles, California. This duo placed the core on a path that would define the group’s early direction.

• The original lineup soon included Ron McGovney on bass and Dave Mustaine on lead guitar, with Cliff Burton replacing McGovney shortly after; Mustaine was later replaced by Kirk Hammett.

• They began by carving out a place in the underground and tape-trading scenes before recording their debut album, Kill 'Em All, in 1983 after moving to the Bay Area.

If you’d like, I can pull up more sources or provide a concise timeline of key milestones from formation through their major album releases.