Midgard

Midgard, "the middle enclosure", is the world of human beings in Norse cosmology, and its name states its place: it lies in the middle of the Nine Worlds, between the divine realm of Asgard above and the shadowed underworlds below, joined to Asgard by the rainbow bridge Bifrost. The Eddas describe its making from the body of the primordial giant Ymir, slain by Odin and his brothers: from his flesh they formed the earth, from his blood the seas, from his bones the mountains, from his skull the dome of the sky, and, crucially, from his eyebrows they built the wall of Midgard to fence the world of men against the giants of Jotunheim outside.

The human world is thus a protected enclosure carved out of chaos and defended against it. Around it, in the encircling ocean, lies coiled the World Serpent Jormungandr, so vast it grips its own tail and rings the whole of Midgard, and at Ragnarok the serpent will rise from the sea, and Thor will kill it and be killed by its venom in the same encounter. Midgard is, in short, the fragile middle ground of the Norse cosmos: the ordered home of humanity, walled against the wild, ringed by a monster, and destined to be unmade and, the sources add, reborn.

Midgard is the one name in this cosmology that survived into ordinary English. Old English has middangeard, which appears in Beowulf and in Christian poetry with no pagan sense left in it, meaning simply the world people live in. Gothic has midjungards. Old Saxon and Old High German have their own forms. The word is common Germanic and older than any surviving Norse text, which suggests the idea of an enclosed middle yard is not a late poetic invention.

The enclosure is literal in the myth. Midgard is made from the body of the giant Ymir, and its defensive wall is built from his eyebrows, which places human habitation inside a fortification made out of a dismembered enemy. Outside it is Utgard, the outer yard, where the giants are. That inside and outside distinction organises much of the mythology, and it maps directly onto the Norse farm with its enclosed home field and the wild beyond.

Tolkien, a philologist by trade, took middangeard and rendered it Middle-earth, which is why the word is now attached to a twentieth century fiction in most readers' minds. He was translating rather than inventing, and the sense he kept, an inhabited middle region with older and stranger things around its edges, is the sense the Germanic sources had.