Anyone who reads Old English poetry will soon enough encounter the word wæl, which means "slaughter". (There are a lot of fights in Old English poetry.) In poetic senses, it was also used for "battlefield" or sometimes metaphorically for those who had been slain in battle (hold that thought).
Naturally, there are compounds:
- wælsceaft: "slaughter-shaft" = spear
- wælstow: "slaughter-place" = battlefield
- wælfus: "slaughter-eager" = ready for death
- wældreore: "slaughter-gore" (dreore gave us "dreary", originally meaning "bloody; gory")
... and many more.
Ok. The word wæl died out in English, and we don't have any words today that directly descend from it. But the word also appeared in other Germanic languages, like Old Norse, which kindly lent us some words that are relatives of wæl.
One is Valhalla, the place in Norse mythology where slain heroes go. Although this concept wasn't widespread in Saxon thinking (apparently), you can see the etymological connection to wæl + hall, where wæl here refers to those who have been slain.
Another wæl-ish borrowing is Valkyrie, who are "maidens of Odin" (M-W) who conduct those slain heroes to Valhalla. The Norse/Germanic roots are again val, a relative of wæl, plus kyrie. The word kyrie is an inflection of the verb for "to choose" (ceosan in Old English).[1] So literally "slaughter-choosers".
That was in Old Norse mythology; whatever the Saxons might have believed about slaughter-choosers, walkyrie took on the meaning of "a malevolent goddess or female demon", used as an Anglisc translation for e.g. the Furies of classical mythology.
As with wæl, the word walkyrie died out in English before the time of Shakespeare. I think we can have some confidence that any use of Valkyrie in modern English probably has something to do with Wagner and the Ring Cycle, for better or worse. :)
I'm not familiar with fantasy literature, so I would not be the slightest bit surprised to learn that "wæl", or some version of it, is used inventively by authors like Tolkien in that genre. Perhaps someone can fill me in.
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