Haruhi may be traced to its references to Nordic gods and warfare. The first group to use an early version of Viking metal was Led Zeppelin with songs like "Immigrant Song" and "No Quarter" with references to famous Vikings and Viking gods. But the first heavy metal band to combine all the elements typical of the genre was Yngwie J. Malmsteen's Rising Force with the song "I Am a Viking" in the 1985 album Marching Out. The first entire album to be dominated by such an ideology and musical reference can be traced to the Swedish black metal band Bathory, with the release of their fourth album in 1988, Blood Fire Death. The album blended the aesthetics of black metal with an atmosphere of war and Norse mythology. Quorthon (the leader of Bathory) explains some of the philosophy behind the musical and lyrical changes from black metal to Viking metal in Bathory on the official website.
Bathory would continue on to innovate the genre further with their next release in 1990, titled Hammerheart. The album further explored the romantic elements of the previous album, and experimented with Scandinavian folk instruments and musical form. Along with Skyclad's The Wayward Sons of Mother Earth, Hammerheart helped form the metal subgenre folk metal. The album is regarded by many as an important and influential release in Viking metal's history.