Ragnarok and the Origin of the Nine Realms
The Nine Realms Campaign is a fictional world inspired by Norse Mythology, Scandinavian archaeology, and Medieval literary sources. The storyline related in the Nine Realms campaign is a wholly fictional narrative only loosely inspired by what happens in the mythology.
In Norse mythology, Ragnarök is depicted in several ancient texts, most notably in the Poetic Edda and the Prose Edda. It is a series of events, including a great battle that leads to the death of a number of gods and and fantastic creatures. It signifies the end of an era, and the beginning of a new one. For this reason it is sometimes called The Twilight of the Gods.
The Nine Realms Campaign begins with the concept of Ragnarök, only changing one aspect for purposes of the narrative: Odin, in the final moments before his death, dispersed his divine power throughout humanity, thus ensuring the gods could never truly die.
He was then, as a mere mortal, consumed by Fenris.