Wikipedia
Wardruna
Wardruna is a musical project based on Nordic spiritualism and the runes of the Elder Futhark. It was started by Einar "Kvitrafn" Selvik in 2003, along with Gaahl and Lindy Fay Hella.
The band began in 2003 and have since released two albums, each based on a set of runes.
There are plans to release at least one more disc, based on eight additional runes. The planned third album will be titled Runaljod - Ragnarok and is set for release on October 26.
In 2014, Kvitrafn announced on the group's official Facebook page that they would take part in composing the score for season 2 of Vikings along with Trevor Morris. He later appeared as an actor on the show.