Blashyrkh is a fictional kingdom heavily featured in the lyrics of black metal band Immortal. According to the band's singer and guitarist Abbath, this frozen kingdom was created by the hatred of both himself and Demonaz. It is ruled by a giant raven god called the "Mighty Ravendark". On the album Battles in the North, in the eponymous song, he is referred to as "the Oath of Frost, who sits on the elder raventhrone," and as "the rightful king of the highest halls."
Blashyrkh is eternally covered with frost, snow and winter, as can be learned from the album "At the Heart of Winter":
Blashyrkh mighty be your name victorious a kingdom we made
with strength and pride all the way you are at the heart of winter
The statue watches the kingdom your giant wings make all beneath
I'm staring forth the raventhrone I know I'm at the heart of winter