Avenged Sevenfold is an American rock band from Huntington Beach, California, formed in 1999. The band has achieved mainstream success with their 2005 album City of Evil, which includes singles such as "Burn It Down", "Bat Country," "Beast and the Harlot" and "Seize the Day." The band's success followed with their self-titled album, that includes singles such as "Critical Acclaim", "Almost Easy", "Afterlife", "Scream" and "Dear God".

Avenged Sevenfold emerged with a metalcore sound on their first two albums, but later changed their musical style into a more hard rock approach with City of Evil. 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. They are currently in production of their fifth studio album. During the end of 2009 the death of their drummer and founding member, James "The Rev" Sullivan was announced.

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, 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.

In January 2009, M. Shadows confirmed that the band is writing the follow-up to their self-titled fourth album within the upcoming months. They also announced that they will be playing at Rock on the Range, from May 16–17, 2009. In April 16, they performed a version of Guns N' Roses' "It's So Easy" onstage with Slash, at the Nokia Theater in Los Angeles. M. Shadows was featured on Slash's debut solo album Slash in the song "Nothing to Say".

On December 28, 2009, drummer James "The Rev" Sullivan was found dead at his home at the age of 28, leaving behind a wife. In addition to Jacobson, over 50 musical artists have commented upon the death of Sullivan.

On January 5, 2010 a private funeral was held for The Rev. In attendance were friends of the band, such as the Lostprophets and Brian Haner Sr.. On January 6, 2010, the body of James Sullivan was laid to rest in an undisclosed location.

The band sports a logo known as the "Deathbat". It was originally designed by an artistic high school friend of Avenged Sevenfold, Micah Montague, as seen on the band's first DVD, All Excess. The Deathbat has appeared on all of the band's album covers, many of which were done by Cameron Rackam, a close friend of the band. The Deathbat has developed from just being a skull with bat wings, to sometimes appear as a full "man size" skeleton with bat wings, as it can be seen at the cover of City of Evil. On Sounding the Seventh Trumpet, there are pictures of two people (in which appear to be Cain and Abel), another angel-like human and a semi-opaque Deathbat below it, several Deathbats appear on the back cover of the album as well. The Deathbat also appears on covers of number of singles such as "Bat Country", "Warmness on the Soul" and "Critical Acclaim".