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Hugin and Munin (Huginn and Muninn) are Odin's two ravens, whose names mean "Thought" and "Memory". Each day they fly over all the worlds and come back to tell him everything they have seen.
Who are Hugin and Munin?
Hugin and Munin are the two ravens of Odin. Their names mean 'Thought' and 'Memory'. They sit upon his shoulders, and every morning he sends them out to fly over all the worlds. In the evening they come back and speak into his ears all that they have seen and heard, and so Odin knows the news of every land.
Thought and Memory
In the poem Grímnismál Odin says that he fears for them each day: he worries that Hugin will not come back, but he worries more for Munin. The words are often read as a hint that the ravens are part of Odin's own mind, sent out on the journeys of a trance.
The Raven-God
Because of them Odin is called Hrafnaguð, the Raven-God. Ravens followed armies and fed on the fallen, and the raven banner flown by Viking war-bands carried the promise that Odin was watching.
They belong to Odin.
Questions
What do Hugin and Munin mean?
Thought and Memory.
Why does Odin fear for them?
In Grímnismál he says he fears Hugin may not come back, and Munin even more. It is often read as a hint that the ravens are part of his own mind.