What the sources are
Almost everything we know about Norse myth comes from Iceland in the thirteenth century or slightly earlier, written down by Christians generations after the old religion had ceased. The main sources are the Poetic Edda, a collection of poems preserved mainly in a manuscript known as the Codex Regius, and the Prose Edda of Snorri Sturluson, which retells and organises the stories. The poems may be older than the manuscripts, but how much older is uncertain and debated. Keep this in mind as you read any claim about what the “Norse believed”. Nine is prominent in these sources, though not in the way popular summaries often suggest.
The Nine Worlds
The phrase appears in Voluspa, the poem in which a seeress recounts the history of the cosmos. In an early stanza she says she remembers nine worlds (the Old Norse is niu heima) and the great tree, the measuring tree, beneath the earth. That is the core of the evidence. The poem does not then list nine worlds one by one.
The familiar list is a modern reconstruction put together from names scattered across the Eddas. It usually runs: Asgard, home of the Aesir gods; Vanaheim, of the Vanir; Alfheim, of the light elves; Midgard, the world of humans; Jotunheim, of the giants; Svartalfheim or Nidavellir, associated with dark elves or dwarves; Niflheim; Muspelheim; and Hel. Versions differ on which names to include, on whether Svartalfheim and Nidavellir are the same place, and on whether Niflheim and Hel are separate. Snorri names many of these places but never gives a tidy list of nine. So “the Nine Worlds” is best described as a number the poems state and a list that later readers filled in.
The world tree, Yggdrasil, is connected to the cosmos in the poems, but the sources do not clearly say that each world hangs on a particular branch. Many popular diagrams show more order than the texts supply.
Odin’s nine nights
The best-known nine in the corpus is in Havamal, the poem of sayings attributed to Odin. In stanzas 138 and 139, he says that he hung on a windy tree for nine whole nights, wounded by a spear and given to Odin, himself to himself. He had no food or drink, and he looked downward, took up the runes, and fell back from the tree. The next stanzas describe him learning powerful songs and drinking a precious mead, and growing in wisdom. Scholars have long compared this scene to initiation or to sacrifice, and some have noted similarities with Christian crucifixion imagery. Whether the Christian parallel was borrowed or coincidental is debated.
Other nights and nines
Nine nights appear in several other episodes, which suggests it was a conventional span of time for waiting and travelling:
- Freyr and Gerdr. In Skirnismal, Gerdr tells Freyr’s messenger that she will meet Freyr in a grove called Barri after nine nights. Freyr then complains that the wait is too long.
- Draupnir. Odin’s gold arm-ring is said, in Snorri’s Prose Edda, to drip eight equal rings every ninth night.
- Hermod’s ride. In Snorri’s Prose Edda, the god Hermod rides for nine nights through deep dark valleys to reach Hel’s realm and ask for Baldr’s return.
- Heimdall’s mothers. In Hyndluljod, the god Heimdall is said to have been born of nine mothers, though the poem does not explain who they were.
- Thor’s nine paces. In Voluspa, Thor walks nine paces after killing the Midgard Serpent and then falls dead, poisoned by its venom.
Nine as three threes, a habit linked to the rule of three in other traditions, may help to explain why nine feels natural here, but the texts do not offer that reason themselves. In some cases, nine may simply mean a long period or a full measure.
Ritual nines in outside accounts
Outside accounts add nine-year festivals. Adam of Bremen, writing in the 1070s about a temple at Uppsala in Sweden, says that every nine years a feast was held at which nine males of each kind of creature were sacrificed. Thietmar of Merseburg, writing in the early eleventh century, gives a similar nine-year gathering at Lejre in Denmark. Both authors were Christian clergy writing about a religion they opposed, and neither saw the events described. Their reports could reflect real practice, exaggeration or both, and historians treat them with care.
Language and number
Old Norse niu, “nine”, belongs among the Indo-European numerals, and the word is closely related to English “nine”. That is a point about vocabulary, not belief. The Norse use of nine is best read inside its own sources rather than as proof that nine had a fixed mystical meaning across European cultures.
What can be said
The attested facts are these: the Eddic poems speak of nine worlds without listing them, and they use nine nights as a significant time span in several stories, most famously Odin’s ordeal on the tree. The modern list of nine specific realms, and ideas about what the number meant to the people who first told the stories, are interpretations built on that evidence.