There are 9 bands sharing this name.

1) Samhain was an American punk rock band formed by vocalist Glenn Danzig in 1983, immediately following his departure from the Misfits, and active until 1987. Samhain played in more of a 'deathrock' and heavy metal-infused style of 'horror punk' than Danzig's previous band. Samhain and its successor, Danzig, use the same horned skull image originally drawn by artist Michael Golden for the cover of the 1984 comic book The Saga of Crystar No. 8, published by Marvel. The font often used in the name logo of Samhain, and later Danzig, is taken from the film The Giant Gila Monster.

Danzig took the name of the band from the ancient Celtic New Year, Samhain, the origin of the modern Halloween. The band's name is typically pronounced "sam-hane", though when the word occurs in song lyrics, Danzig himself pronounces it "sah-win," the same as the pronunciation of the eponymous holiday.

Samhain's lyrics were darker than those of the Misfits, with themes rooted in paganism and the occult and eventually the horrors of reality, as opposed to the sometimes cartoonish monster themes of the Misfits. Samhain's musical style was a dark, gritty, and experimental combination of punk, gothic rock, and on the last album, heavy metal.

Discography:
• Initium (1984)
• Unholy Passion EP (1985)
• III: November-Coming-Fire (1986)
• Final Descent (1990)

2) Samhain was a danish Black/Death metal band, who later changed name to Desexult. Samhain released one demo, called "The Courier", in 1985.

3) Samhain is the name of a Celtic folk band.

4) Samhain is a Slovakian industrial act, started in 1997, but managed to release their first full-length album "Violent Identity" only in 2006 at Aliens Productions. Their style can be described as a successful mix of old-school dark electro and idm with a touch of industrial sound.

5) German Thrash Metal band Deathrow were initially called Samhain. Under this name they released 3 demos: The Lord of the Dead (1985), Eternal Death (1986), and Live (1986).

6) Samhain is a Russian satanic black metal band formed in Naberezhnye Chelny by members Death and Carcass. Carcass left to start a solo project, Izgoi.
Official Site

7) Samhain is a female-fronted Czech Melodic Heavy Metal band.
Official Site

8) Samhain is a Russian Death/Symphodeath metal band, formed by former Catharsis members Sergey "Immortal" Bendrickov and Lyudmila Abramova.
Band members:
Sergey "Immortal" Bendrickov - Vocals
Lyudmila Abramova - Vocals
Nicolai Seemonov - Keyboards
Anton Smolyanin - Drums
Roman Guryev - Guitars

Discography:
2000 - Herimos
2002 - Revival
2006 - Epiphany

9) Samhain is also a RAC band from Germany.
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