Twenty five minutes and eleven seconds. That is the length of the last piece on Filosofem, it has no guitar on it, no drums and no voice, and it takes up almost the whole second half of a record that is otherwise a black metal album. Nobody at the time called that atmospheric black metal, because the term did not exist. It is where the style begins all the same.
What separates this branch from everything around it is not the keyboard, the reverb or the forest on the sleeve. It is what the music does to time. A conventional black metal song moves; this one occupies. Where the branch sits relative to its neighbours is drawn on the subgenre map.
Where it starts
Three Norwegian records in three years did the work, and only one of them was trying to. Emperor recorded In the Nightside Eclipse at Grieg Hall in Bergen in July 1993 and released it through Candlelight on 21 February 1994 with keyboards written in the studio because the band had no keyboard player, and the result put a permanent orchestral shadow behind everything the genre did afterwards. Burzum recorded Hvis lyset tar oss in the same building in September 1992, sat on it until April 1994, and proved that a riff repeated for eight minutes without variation is not a failure of writing but a different unit of composition. Ulver then recorded Bergtatt at Endless Lydstudio in Oslo in November and December 1994, released it through Head Not Found in February 1995, and put acoustic guitar, flute, low choirs and clean singing into a black metal record with no anti Christian content anywhere on it.

By 1995 the Austrian duo Summoning had turned away from ordinary black metal entirely and started building records in which the keyboard carries the melody, the drums are programmed from a keyboard rather than played, and the words come out of Tolkien. Four records, four different arguments, and between them the entire vocabulary of what followed.
What the music does to time
The mechanics are consistent enough to list, and every one of them is a decision about duration rather than about mood.
- Songs of eight to twenty minutes, structured in movements rather than in verses and choruses.
- Repetition used to accumulate rather than to exhaust: the same figure returns with one element added each time, and the change is felt before it is noticed.
- The guitar mixed level with or behind the keyboards, so the wall of tremolo functions as a texture and not as the lead voice.
- The vocal pushed deep into the mix, frequently to the point of being one more instrument, which is the exact opposite of what the depressive wing does with it.
- Acoustic guitar, folk instruments and field recordings used as whole sections, not as decoration between the real songs.
- An arrival point held back until the last third, which is why these records reward being played in full and punish being sampled.
The blast beat survives here but changes job. In the second wave it was an accelerator. In this branch it is a sustained flat surface, laid under a slow melody so that speed and stillness happen at the same time, which is the single most distinctive trick the style has and the hardest one to fake.
The production is a decision, not a limitation
The reflex assumption about the raw sound is poverty, and it is wrong more often than it is right. Paysage d'Hiver, the Swiss project started by Tobias Möckl in 1997, has been explicit for nearly thirty years that the atmosphere is the point and that the unpolished sound is chosen, not endured, and the releases have been kept deliberately scarce, cassettes at two hundred copies and vinyl at three hundred, with unlimited compact discs for anybody who only wanted the music. Darkspace, out of the same country, took the opposite direction with the same logic, building a sound so processed and so cold that the records are effectively about vacuum.
Half of this genre's signature guitar tone came out of a stereo amplifier and a headset taken off a helicopter.
America, 1998
The style left Europe through one record made by a band that broke up before anybody heard it. Weakling formed in San Francisco in 1998, recorded Dead as Dreams that same year, split in 1999 without announcing it, and the album finally appeared through tUMULt in 2000: five tracks, every one of them over ten minutes, seventy six minutes in total, Scandinavian black metal run through a sensibility that had clearly spent time with progressive rock records from the seventies. It sold almost nothing at first. Fenriz of Darkthrone called it a masterpiece, the reissue reached the people the first pressing had not, and most of what American black metal became in the following decade is downstream of it.
What the sleeves are doing
No other branch of the genre has so fixed a visual grammar, and it was set before the music was. The cover of Hvis lyset tar oss is a drawing made in 1894 or 1895 by the Norwegian artist Theodor Kittelsen, a figure walking away across open ground, and it belongs to a body of work about plague, poverty and forest that predates black metal by a century. From that one decision comes almost everything the style has done with its packaging since: nineteenth century landscape painting, monochrome photographs of terrain, a horizon with nothing human on it, and the band name set small enough to be unreadable.
This matters more than sleeve design usually does, because the picture is telling the listener how to hear the record. A photograph of a valley instructs you to treat forty minutes of tremolo as weather rather than as aggression, and it does that work before the first note. It is also the reason the style is so easy to counterfeit visually, and why a genuinely good record with an ugly cover struggles here in a way it would not in death metal.
The complaint worth taking seriously
Atmosphere is the easiest thing in music to counterfeit. A long reverb, a slow tremolo figure, a photograph of a mountain and eleven minutes of running time will produce something that sounds like this style to anybody not listening closely, and a large proportion of what is released under the tag every month is exactly that. The word itself has become an alibi: a record with no melodies, no arrangement and no arrival gets defended on the grounds that it was never about riffs.
The test is whether the eleven minutes are used. Put the needle down at minute eight and ask whether anything has happened since minute two. On Dead as Dreams, on Hvis lyset tar oss, on the better Summoning records, a great deal has happened and most of it was gradual enough to be invisible while it occurred. On the imitations nothing has happened at all, and the length is the whole idea rather than the vehicle for one.
The second complaint is more recent and harder to answer. Since about 2010 a substantial part of this music has become pleasant. Warm production, major key melodies, clean singing, a record you can work to. There is nothing wrong with any of that except the name it is being sold under, and the bands doing it best are usually the ones who stopped claiming to be black metal at all.
What it grew into
From roughly 2004 onward the style became the most geographically spread branch the genre has, with major records out of Ukraine, Switzerland, Australia, Scotland, the American Pacific Northwest and the Appalachians, most of them made by one or two people with no scene around them. The names worth starting with, and the reasons, are in atmospheric Black Metal Bands. How this branch grew out of the second wave, and what the second wave was reacting to in turn, is told in black metal, chapter by chapter.