- Parents were devout Christian Scientists.
- Played in several hard rock groups as a teenager, including Obsession, Phantom Lord and Leather Charm.
- Cofounded Metallica with drummer Lars Ulrich in 1981; the band released its debut, landmark thrash album Kill 'Em All, in 1983.
- Rose to international fame with Metallica's 1991 self-titled album, which sold more than 14 million copies and featured the hits "Enter Sandman" and "Nothing Else Matters."
- Was badly burned in a pyrotechnic accident during a 1992 Metallica concert.
- Provided a rare look into his personal life with the acclaimed documentary Some Kind of Monster (2004), which dealt with intra-band struggles during the making of Metallica's St. Anger (2003).
- Inducted into the Rock and Roll Hall of Fame as a member of Metallica in 2009.
- Is an avid hot rod and motorcycle enthusiast.