Enslaved - Sigmundskvadet (feat. HOV and Trygve Mathiesen)
This is the bonus track from the 2001 Enslaved album, Monumension.
The YouTube user hensch1974 has provided the lyrics to the old version of this song and the new version (this one) which you can get the here:
They also said “This is a old faroeese song about a Viking chief that made faroe island christian and was murded by a nother Chief called trøndur that belived in the old ASE (Odin & Thor)“
About the monument from Wikipedia:
Sverd i fjell (English: Swords in Rock) is a monument in Hafrsfjord, Norway.
The monument was made by sculptor Fritz Røed from Bryne and was opened by Olav V of Norway in 1983. Three large swords stand on the hill as a memory to the Battle of Hafrsfjord in year 872, when King Harald Fairhair gathered all of Norway under one crown.
The largest sword represents the victorious king, and the two smaller swords represent the defeated kings. The monument also represents peace, as the three swords are stuck in the hill and will never be used again.
Thanks to hensch1974 for providing the lyrics and info and thanks to Enslaved, HOV and Trygve Mathiesen for performing it.