Aegir (pronounced “EYE-gir;” Old Norse Ægir) and Ran (pronounced “RAN;” Old Norse Rán) are two of the most often-mentioned giants in Norse mythology. Unfortunately, as fragmentary as the sources for our knowledge of Norse mythology are, that doesn’t come out to a particularly large number of mentions. Still, some of the most general characteristics attributed to Aegir and Ran by the pre-Christian Norse can be discerned.
Aegir and Ran are, respectively, husband and wife. They dwell in a magnificent hall beneath the ocean, and can be seen as the divine powers of the ocean and its varying qualities. Aegir (“Ocean”), who is often portrayed as a gracious host, seems to correspond to its more benevolent aspects. Ran (“Robber”) seems to correspond to its more sinister aspects; in Old Norse poetry, she’s usually mentioned in the context of drowning unfortunate seafarers and dragging them down to dwell in her underwater abode.
While the relationship between the Aesir gods and the giants is ambivalent at best, and often marked by considerable strife, Aegir and Ran enjoy an overwhelmingly friendly relationship with the gods. The gods are apparently regular guests at Aegir’s magnificent feasts.
Together the couple has nine daughters, who are usually interpreted as being spirits of the waves.
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 Simek, Rudolf. 1993. Dictionary of Northern Mythology. Translated by Angela Hall. p. 260.