In Norse mythology, the apocalyptic event is called Ragnarok.
The Old Norse name Ragnarök is commonly translated as “fate of the gods” or “doom of the gods.” It describes a sequence of catastrophic events, including a great battle, the deaths of major gods, natural disasters, and the submersion of the world in water.
Ragnarok is not simply the end of everything. In the surviving myths, the world eventually emerges again, and some gods and two human survivors remain to continue life. This cycle of destruction and renewal distinguishes Ragnarok from a purely final apocalypse.
The story appears most fully in the Poetic Edda and Prose Edda, medieval Icelandic works that preserve earlier Norse traditions. The related German term Götterdämmerung belongs especially to later Germanic and Wagnerian usage, while Fimbulwinter names only the terrible winter preceding the final conflict.