Def Leppard are an English rock band formed in 1976 in Sheffield. Since 1992, it has consisted of Rick Savage (bass, backing vocals), Joe Elliott (lead vocals), Rick Allen (drums), Phil Collen (guitar, backing vocals), and Vivian Campbell (guitar, backing vocals). They established themselves as part of the new wave of British heavy metal of the early 1980s. 

Their greatest commercial success came between the early 1980s and early 1990s.The band's first album, 1980's On Through the Night, reached the Top 15 in the UK but received little notice elsewhere. Their second album, 1981's High 'n' Dry, was produced by Mutt Lange, who helped them to define their melodic hard rock style. 

The album's most popular track "Bringin' On the Heartbreak" became one of the first rock videos played on MTV in 1982, but the album reached only the Top 30 and 40 in the UK and US. Their next studio album, Pyromania, was released in January 1983, with "Photograph" and "Rock of Ages" both topping the US Rock Tracks chart and reaching the top 20 of the Hot 100. 

Reaching No. 2 on the US album chart, Pyromania was certified Diamond in the US. It reached the top 20 in the UK but did not sell much elsewhere.

The band's fourth album, the more pop-oriented Hysteria (1987), topped the UK, US, Canadian and Australian charts. It has been certified 12× platinum for sales in the US, selling over 25 million copies worldwide, making it one of the best-selling albums of all time.

It spawned six Top 20 US singles, including the US Billboard Hot 100 No. 1 "Love Bites", alongside "Pour Some Sugar on Me" (US No. 2), "Hysteria", "Armageddon It", "Animal" (at No. 6, the biggest UK hit), and "Rocket" (a Top 15 hit in many countries).

Their next studio album, Adrenalize (their first following the death of guitarist Steve Clark), reached No. 1 on the UK, US and Australian charts in 1992. It contained several hits, including the US Rock Tracks chart-topper "Let's Get Rocked", which became their biggest hit in several countries, including No. 2 in the UK. 

The third single, "Have You Ever Needed Someone So Bad", was a Top 15 song in the US, UK and Canada. Adrenalize went on to sell over eight million copies worldwide. Their 1993 album, Retro Active, contained the acoustic Top 5 North American hit "Two Steps Behind". 

Their greatest-hits album Vault, released in 1995, featured the UK No. 2 hit "When Love & Hate Collide" and reached the Top 10 in several countries, going 5× platinum in the US. Beginning with Slang, Def Leppard released five albums between 1996-2008, with most usually reaching the Top 15 in several countries, including the UK, US and Canada. 

Their self-titled album, released in 2015, reached the Top 10 in several countries. Their newest studio album, Diamond Star Halos, was released in May 2022 and reached the Top 10 in the US, UK and Australia.

As one of the world's best-selling music artists, Def Leppard have sold more than 100 million records worldwide, and have two albums with RIAA diamond certification: Pyromania and Hysteria, making them one of only five rock bands with two original studio albums selling more than 10 million copies in the US.

 

The band were ranked No. 31 in VH1's "100 Greatest Artists of Hard Rock" and No. 70 in "100 Greatest Artists of All Time". They were inducted into the Rock and Roll Hall of Fame in 2019.

The Adrenalize World Tour – also known as the Adrenalize "Seven Day Weekend" Tour – was a concert tour by English hard rock band Def Leppard to support the Adrenalize album, released in March 1992. It was their first tour without guitarist Steve Clark, who died in January 1991 while the album was recorded. 

Former Dio and Whitesnake guitarist Vivian Campbell joined six weeks before the tour began.[The tour kicked off with a club show in Dublin, Ireland on April 15, 1992. Campbell's first public appearance with the band, it was a warm-up for The Freddie Mercury Tribute Concert on April 20 in London.

In 1992 and early 1993, the tour was performed in the round, with the stage surrounded by the audience; a format Leppard first used on the 1987/1988 Hysteria World Tour.

"We started the tour as a huge, long-haired, dressed-up, arena rock band," Campbell observed, "and we finished it looking like Pearl Jam: wearing ratty jeans, growing goatees and cutting our hair. During the course of that fifteen-month tour, the entire musical landscape changed."