Avenged Sevenfold emerged with a metalcore sound on their debut Sounding the Seventh Trumpet[citation needed], which included screaming vocals and heavy guitar riffs. The band changed their style on their third release, City of Evil, which features more of a mainstream hard rock style.[citation needed] The band continued to explore new sounds with their self titled release and enjoyed continued mainstream success before their drummer, James Sullivan, "The Rev" died of a drug overdose in 2009. Despite this setback, the band continued on with Dream Theater drummer Mike Portnoy and released their fifth album Nightmare in 2010.

Avenged Sevenfold has released five studio albums, one live album/compilation, and fifteen singles. The band themselves have received much credit for their worldwide mainstream success and were most notably proclaimed as one of the leaders and key bands in the New Wave of American Heavy Metal and were featured as second place on Ultimate Guitar's Top Ten Bands of the Decade.

The band was formed in 1999 in Huntington Beach, California with original members M. Shadows, Zacky Vengeance, The Rev and Matt Wendt. M Shadows came up with the name as a reference to the story of Cain and Abel from The Bible, which can be found in Genesis 4:24, although they are not a religious band. Upon its formation, each member of the band also took on a pseudonym which were already nicknames of theirs from high school. Before release their debut album, the band recorded two demos in 1999 and 2000. Avenged Sevenfold's debut album, Sounding the Seventh Trumpet, was recorded when the band members were just eighteen years old and in high school. It was originally released on their first label, Good Life Recordings in 2001. After lead guitarist Synyster Gates joined the band, at the end of 1999 when he was 18 at the introductory track "To End the Rapture" was re-recorded featuring a full band element. The album was subsequently re-released on Hopeless Records in 2002.

The band started to receive recognition, performing with bands such as Mushroomhead and Shadows Fall and playing on the Take Action Tour. Having settled on their fourth bassist, Johnny Christ, they released Waking the Fallen on Hopeless Records in August 2003. The album featured a more refined and mature sound production in comparison to their previous album. The band received profiles in Billboard and The Boston Globe, and played in the Vans Warped Tour. In 2004, Avenged Sevenfold toured again on the Vans Warped Tour and recorded a video for their song "Unholy Confessions" which went into rotation on MTV2's Headbanger's Ball. Shortly after the release of Waking the Fallen, Avenged Sevenfold left Hopeless Records and were signed to Warner Bros. Records.

City of Evil, the band's third album and major label debut, was released on June 7, 2005 and debuted at #30 on the Billboard 200 chart, selling over 30,000 copies in its first week of release. It utilized a more classic metal sound than Avenged Sevenfold's previous albums, which had been grouped into the metalcore genre. The album is also notable for the absence of screamed and growled vocals; M. Shadows worked with vocal coach Ron Anderson—whose clients have included Axl Rose and Chris Cornell—for months before the album's release to achieve a sound that had "grit while still having the tone". The album received steller reviews from several magazines and websites and is credited for propelling the band into international popularity.

After playing Ozzfest in 2006, Avenged Sevenfold memorably beat out R&B Singers Rihanna and Chris Brown, Panic! at the Disco, Angels and Airwaves and James Blunt for the title of Best New Artist at the MTV Video Music Awards, thanks in part to their Fear and Loathing in Las Vegas-inspired song “Bat Country.”

They returned to the Vans Warped Tour, this time headlining and then continued on their own "Cities of Evil Tour." In addition, their lead single "Bat Country" reached #2 on Billboard's Mainstream Rock Charts, #6 on Billboard's Modern Rock Charts and the accompanying video made it to #1 on MTV's Total Request Live. Propelled by this success, the album sold well and became Avenged Sevenfold's first gold record. It was later certified platinum in August 2009.

Avenged Sevenfold's mainstream success got them an invitation to 2006's Ozzfest tour on the main stage, alongside other well known hard rock and heavy metal acts DragonForce, Lacuna Coil, Hatebreed, Disturbed and System of a Down. That same year they also completed a worldwide tour, including the US, The United Kingdom (as well as mainland Europe), Japan, Australia and New Zealand. After being on tour for sixteen months in promotion of City of Evil, the band announced that they were cancelling their Fall 2006 tour in favor of recording new music. M. Shadows stated that their fourth studio album—which the band self-titled and self-produced—would not be a "City of Evil Part 2" or "Waking the Fallen Part 2," but would incorporate a new, grittier sound. To tide the fans over in between albums, the band released their first DVD titled All Excess on July 17, 2007. All Excess, which debuted as the #1 DVD in the USA, included live performances and backstage footage that spanned the band's eight year career. Two tribute albums, Strung Out on Avenged Sevenfold: Bat Wings and Broken Strings and Strung Out on Avenged Sevenfold: The String Tribute were also released in October 2007.

Avenged Sevenfold, the band's fourth album, was released on October 30, 2007, debuting at #4 on the Billboard 200 with over 90,000 copies sold. Two singles, "Critical Acclaim" and "Almost Easy" were released prior to the album's debut. In December 2007, an animated video was made for "A Little Piece of Heaven." Due to the song's controversial subject matter, however, Warner Brothers only released it to registered MVI users over the internet. The third single, "Afterlife" and its video was released in January 2008. Their fourth single, "Dear God", was released on September 30, 2008. Although critical reception was generally mixed the self-titled album went on to sell over 500,000 copies and was awarded "Album of the Year" at the Kerrang! Awards.

Avenged Sevenfold headlined the 2008 Taste of Chaos tour with Atreyu, Bullet for My Valentine, Blessthefall and Idiot Pilot. They used the footage from their last show in Long Beach for Live in the LBC & Diamonds in the Rough, a two-disc B-sides CD and live DVD which was released on September 16, 2008. They also recorded numerous covers, including Pantera's "Walk", Iron Maiden's "Flash of the Blade" and Black Sabbath's "Paranoid". They will also be releasing a Guitar Tutorial DVD, which include the five tracks, Afterlife, Almost Easy, Bat Country, Beast and the Harlot and Trashed And Scattered, breaking down the guitar solos and riffs in each song.