Common traits include a slow-paced and heavy riffing style, anthemic choruses, use of both clean and harsh vocals, a reliance on folk instrumentation, and often the use of keyboards for atmospheric effect.
Though artists such as Led Zeppelin, Yngwie Malmsteen, Heavy Load, and Manowar have previously dealt with Viking themes, Bathory from Sweden is generally credited with pioneering the style with its albums Blood Fire Death (1988) and Hammerheart (1990), which launched a renewed interest in the Viking Age among heavy metal musicians.
Enslaved, from Norway, followed up on this burgeoning Viking trend with Hordanes Land (1993) and Vikingligr Veldi (1994).
Burzum, Emperor, Einherjer, and Helheim, among others, helped further develop the genre in the early through mid-1990s.
Through the work of artists such as the German project Falkenbach, Viking metal soon spread from the Nordic countries to other nations with Viking history or an even broader Germanic heritage, and has since influenced musicians across the globe.