Black metal is a musical genre which emerged in the early 1980s predating the great expansion of heavy metal 'extreme' genres. Black metal evolved from thrash metal, as did its sister genre death metal.
There are two views on the genre. One views black metal as a very specific form of music that must adhere to a particular 'style' in order for it to be a part of the genre; while the second considers the lyrical and philosophical/political ideology of the music to take more precedence in defining the genre itself, rather than 'style'.
The main originators of black metal are considered to be the bands Venom (who coined the term in 1981 and named their second album Black Metal in 1982), Mercyful Fate, Bathory, Hellhammer, Bulldozer, Celtic Frost and Mayhem. Albums that first sounded like what is generally considered to be black metal today are considered to be the recordings of Bathory in the mid 1980s, most notably Under the Sign of the Black Mark.
Black metal congealed in its current form (known as the second wave of black metal, which is rooted much more heavily in classical musical theory) through the influence of Norwegian bands such as Darkthrone, Enslaved, Burzum, Mayhem, Immortal, and Emperor, who began with the earlier style and introduced elements from mainstream heavy metal, classical music and popularised the style to a growing underground audience. Their influence is most apparent in the Satanic (or other various pagan) imagery, anti-Christian lyrics and occult themes.
In the late 1980's and early 1990's, one of the most prominent figures of the Norwegian scene was Øystein Aarseth, better known as Euronymous, the guitarist in Mayhem.
The scene was deeply anti-Christian: it had a stated goal of removing the influence of Christianity and other non-Scandinavian religions from Norwegian culture and effecting a return to the nation's Norse roots. One minority current, associated with NSBM, included an element of unashamed anti-Semitism. The movement was largely directed by an 'Inner Circle', made up of Aarseth and a few close friends, from the basement of Aarseth's record store, Helvete (Hell). That location also housed a recording studio, where records were made by Mayhem and a number of other bands that were signed to Aarseth's independent label, Deathlike Silence Productions. Deathlike Silence's stated goal was to release records by bands "that incarnated evil in its most pure state."
Also around this time, there was a rash of arsons directed at Christian churches in Norway—many of the buildings were hundreds of years old, and widely regarded as important historical landmarks—that Aarseth's circle claimed responsibility for inspiring, if not necessarily perpetrating. The most notable church was Norway's Fantoft stave church, which was burned by a member of Euronymous's inner circle; the man behind the one-man band Burzum, Varg Vikernes, aka "Count Grishnackh", who also played bass guitar for Mayhem. Black metal enthusiasts also started to terrorize other notable "death metal" bands that were touring their country or in neighboring countries, on the basis of their lack of apparent "evilness". Many recall a strong Swedish death metal and Norwegian black metal rivalry.
By the last few years of the 1990s, the black metal scene had lost much of the violence that seemed to be attached to it in the early days of the scene. Also, bands begun to make records with higher production-quality.
However, since the mid-90s, an Eastern European black metal scene has been developing. Bands from these former Iron Curtain lands are recording albums more in keeping with the primitive nature of the early Norwegian artists. Many of these bands' lyrics glorify the pagan roots of their home countries, occasionally injecting elements of indigenous folk music into their arrangements. The Latvian band Skyforger is a prime example of this new aesthetic. The black metal scene in Russia and Ukraine has produced many bands more in keeping with the carefully arranged sounds coming from Scandinavia, but with more appreciation for the low fidelity aesthetic of early black metal. The Czech band Trollech are a perfect example of the "old-school" Pagan black metal band. The Ukrainian neo-Nazi Nokturnal Mortum has achieved very large recognition in the west; their earlier albums relied heavily on synthesizers, but their current work has a grimmer, more abrasive feel flavored with Slavic folk instruments. Poland's neo-Nazi band Graveland has, in recent albums, striven for a 'medieval' feel, much like a much more developed version of later 'viking' Bathory albums, but in the past made much rawer music which still held a certain intangible folk flavor. From Romania, Negura Bunget is a prime example of traditional black metal, injecting their own indigenous mix of Dacian and Latin elements, along with a Scandinavian sound. Also, notable are Serbian elite bands - The Stone and May Result. There is also a growing number of American bands playing black metal (sometimes called USBM bands). This movement has not taken a particularly clear form, but better-known groups are Typhus, Fog, Judas Iscariot, Absu, Krieg, Grand Belial's Key, Goatwhore, Kult ov Azazel, Choronzon (Music project), Xasthur, Leviathan, and the death metal-influenced Acheron and Averse Sefira.