Tradition: Norse mythology
Alternative Names: Níðhǫggr, Níðhöggr, Nidhöggur, Nidhug
Category: Dragon
The Myth
Nidhogg is a terrible dragon or serpent that dwells beneath Yggdrasil, the great World Tree. He gnaws endlessly at one of the tree’s great roots, the root that stretches over Niflheim. Beneath the world tree, he continually tears at its foundations while other creatures inhabit the branches above.
Nidhogg is also associated with the dead and the dark realms beneath the world. In the halls of Náströnd, where the wicked dead suffer, venom falls through the roof and the hall is woven from serpents’ spines. There Nidhogg feeds upon the corpses of those who committed murder, broke oaths, or betrayed those who trusted them. He is described as a creature of malice, a monstrous serpent that consumes the dead.
High above him, an eagle dwells among the branches of Yggdrasil. Between the eagle and Nidhogg runs the squirrel Ratatoskr, carrying hostile and envious words between the two creatures as it travels up and down the World Tree. Thus the great dragon beneath the roots is locked into an ancient struggle with the creature above.
Nidhogg’s most ominous appearance comes at the end of Völuspá. After the events surrounding Ragnarök, a dark dragon comes flying from the direction of Niðafjöll, described as a gleaming serpent carrying the corpses of the dead in its wings. The dragon is Nidhogg, rising from the darkness with the bodies of the dead as the world sinks. The meaning of this final appearance is uncertain, but it is commonly understood as an ominous image connected with Ragnarök.
His name itself is connected with biting or striking, and may evoke malice, darkness, or the act of gnawing below the roots of Yggdrasil. Whatever its precise meaning, Nidhogg’s role is unmistakable: beneath the World Tree waits a monstrous serpent, endlessly gnawing at its roots and feeding upon the dead.
Sources
“Níðhöggr.” Wikipedia: The Free Encyclopedia. Wikimedia Foundation. Accessed October 2, 2026. https://en.wikipedia.org/wiki/Nidhogg