Metallica were formed in Los Angeles, California, in early 1981 when drummer Lars Ulrich placed an advertisement in L.A. newspaper The Recycler, and received replies from guitarists James Hetfield and Hugh Tanner of Leather Charm. Ulrich then asked Metal Blade Records founder Brian Slagel if he could record a song for the label's upcoming compilation “Metal Massacre”. Slagel accepted, and Ulrich recruited Hetfield to sing and play rhythm guitar. 2 names for the new band were proposed by Ron Quintana (who was brainstorming names for a fanzine) - Metal Mania and Metallica, with Ulrich settling on the latter. A second advertisement was placed in The Recycler for the position of lead guitarist, answered by Dave Mustaine – on seeing his expensive guitar equipment, Ulrich and Hetfield recruited him.

In early 1982, Metallica recorded its first original song "Hit the Lights" for the “Metal Massacre I” compilation with Hetfield playing bass and Lloyd Grant credited with a guitar solo. The band played its first live show in March, at Radio City in Anaheim, California, with newly recruited bassist Ron McGovney, and subsequently produced their first demo “Power Metal”. Later that year, Ulrich and Hetfield attended a show at the nightclub Whisky a Go Go, which featured bassist Cliff Burton in a band called Trauma. They were ‘blown away’ by Burton's use of a wah-wah pedal and asked him to join Metallica (Hetfield and Mustaine wanted McGovney out as they thought that he ‘didn't contribute anything, he just followed’). Burton initially declined the offer, but by the end of the year he had accepted on the condition the band move to San Francisco.

Thus Metallica was ready to record its debut album, and concert promoter Johnny "Z" Zazula, who had heard the band’s 1982 “No Life 'til Leather” demo, ended up borrowing money to cover the recording budget, and signed Metallica to his own label, Megaforce Records. Mustaine was then kicked out of the band due to drug and alcohol abuse, and violent behavior, and Exodus guitarist Kirk Hammett flew in to replace him the same afternoon. In 1983, the band recorded their debut, “Metal Up Your Ass”, produced by Paul Curcio, however, due to conflicts with the band's record label and the distributors' refusal to release an album with that name, it was renamed “Kill 'Em All”. It peaked on the Billboard 200 at number 120.

Metallica recorded their second studio album, “Ride the Lightning”, at Sweet Silence Studios in Copenhagen, Denmark. Released in August 1984, it peaked at number 100 on the Billboard 200. After attending a Metallica gig the following month, Elektra Records A&R director Michael Alago signed Metallica to Elektra Records. Third studio album “Master of Puppets” was also recorded at Sweet Silence Studios, and was released in March 1986. It peaked at number 29 on the Billboard 200, spending 72 weeks on the chart, and was the band's first to be certified gold (it was eventually certified 6 times platinum in 2003).

On September 27, 1986, during the European leg of their Damage Inc. tour, Metallica drew cards to see which bunk of the tour bus they would sleep in. Burton won and chose to sleep in Hammett's bunk. Around dawn near Dörarp, Sweden, the bus driver lost control and skidded, which caused the bus to flip several times. Ulrich, Hammett, and Hetfield sustained no serious injuries, but bassist Burton was pinned under the bus, and was killed. His death left the band’s future in doubt, but the 3 remaining members decided that Burton would want them to carry on, and with the Burton family's blessings, the band sought a replacement. Around 40 people auditioned, including Hammett's childhood friend Les Claypool of Primus, Troy Gregory of Prong, and Jason Newsted, formerly of Flotsam and Jetsam. Newsted learned Metallica’s entire setlist, and the band decided that he was the one to replace Burton. In August 1987 an all-covers EP titled “The $5.98 E.P.: Garage Days Re-Revisited” was released, recorded in an effort to utilize the band's newly constructed recording studio, test out the talents of Newsted, and to relieve grief and stress following Burton’s death. A video entitled “Cliff 'Em All” was released also in 1987 commemorating Burton's 3 years in Metallica, with footage including bass solos, home videos, and pictures. “…And Justice for All”, the band's first studio album since Burton's death, was released in 1988 peaking at number 6 on the Billboard 200, their first Top 10. It was certified platinum 9 weeks after its release, and earned Metallica a 1989 Grammy Award nomination for “Best Hard Rock/Metal Performance Vocal or Instrument”.

In October 1990, Metallica entered North Hollywood’s One on One studio with producer Bob Rock (The Cult, Bon Jovi, Mötley Crüe). ”Metallica” (also known as ”The Black Album”) was remixed 3 times, cost $1 million, and ended 3 marriages. Released in 1991, ”Metallica” peaked at number 1 on the Billboard 200, shifting over 650,000 copies in its first week. It has since been certified 15 times platinum in the US, making it the 25th highest-selling album in the country.

After 3 years touring in support of ”Metallica”, the band then spent roughly a year writing and recording new songs, resulting in the release of “Load” in 1996, which entered the Billboard 200 and ARIA Charts at number 1. During early production of “Load”, the band had produced enough material for a double album, thus it was decided that half of the songs were to be released, and the band would continue to work on the remaining songs and release them the following year. This resulted in the follow-up album, “ReLoad”, which peaked at number 1 on the Billboard 200, and number 2 on the Top Canadian Album chart.

In 1998, Metallica compiled a double album of cover songs entitled “Garage Inc.”, with the first disc containing newly recorded covers by bands such as Diamond Head, Killing Joke, The Misfits, Thin Lizzy, Mercyful Fate and Black Sabbath, and the second disc featuring the original “The $5.98 E.P.: Garage Days Re-Revisited”. The album entered the Billboard 200 at number 2. A year later, Metallica recorded 2 performances with the San Francisco Symphony Orchestra conducted by the late Michael Kamen - the audio recording and concert footage were released as the album and concert film “S&M”, which entered the Billboard 200 at number 2, and the Australian ARIA charts and Top Internet Albums chart at number 1.

In January 2001, bassist Jason Newsted left the band, due to "private and personal reasons, and the physical damage I have done to myself over the years while playing the music that I love". 6 months later, just before entering the recording studio, Hetfield entered rehab due to "alcoholism and other addictions". All recording plans were put on hold and the band's future was in doubt. However, on Hetfield’s return in December 2001, the band returned to the recording studio. Following ”St. Anger”’s completion in early 2003 (with Bob Rock filling in on bass), the band held auditions for Newsted's permanent replacement. After 3 months, Robert Trujillo, formerly of Suicidal Tendencies and Ozzy Osbourne's band, was chosen as the new bassist (ironically, Newsted joined Canadian thrash metal band Voivod in 2002, and was Trujillo's replacement in Osbourne's band during the 2003 Ozzfest tour, which included Voivod as part of the touring bill). ”St. Anger”’s debuted at number 1 on the Billboard 200 in June 2003, with the title track winning the 2004 Grammy Award for “Best Metal Performance”.

In December 2006, Metallica released a DVD containing all the music videos from 1989 to 2004 (thoughtfully titled “The Videos 1989-2004”). It sold 28,000 copies in its first week, and entered the Billboard Top Videos chart at number 3. They also recorded a cover of Ennio Morricone's "The Ecstasy of Gold" for a tribute album entitled “We All Love Ennio Morricone”, released in February 2007 – the cover received a Grammy nomination at the 50th Grammy Awards for "Best Rock Instrumental Performance". Around this time the band also announced that producer Bob Rock was stepping down, and that their ninth studio LP would be produced by Rick Rubin (Danzig, Slayer, Slipknot, System of a Down). The resultant “Death Magnetic” was released in September 2008, debuting at number 1 in the Australian, Canadian, Mexican, European and US album charts (selling 490,000 copies in the US and making Metallica the first band to have 5 consecutive studio albums debut at number 1 in the history of the Billboard 200).

Metallica have sold more than 90 million records worldwide, including 57 million in the US.