More creatures of folklore!
A Valkyrie is a corpse goddess from Nordic mythology. The name translates to “chooser of the slain” and has a very similar story to the Morrigan from Celtic folklore. They are described as viking-like women that decide who will die in battle. Those who are selected are brought to to Valhalla- the afterlife “hall of the slain”.
These beautiful creatures are often depicted as loving helpers, but also as evil grim reapers… depends which Nordic poems you’re reading. They are associated with ravens (like the Morrigan) and sometimes swans.
Although they are painted as gorgeous women in heavy armor, they do not engage in battle. They are merely servant maidens of the god, Odin. Odin’s story is a bit confusing, but from what I gather- he is a German/Nordic God of healing, death, royalty, knowledge, battles, poetry, and sorcery. He is the ruler of the Valkyrie and Valhalla.
There’s a great article with much more information here: http://www.timelessmyths.com/norse/valkyries.html
and a book that looks pretty interesting on Viking Mythology here: http://www.amazon.com/Viking-Mythology-Thor-Norse-Myths-ebook/dp/B00MGU42LU/ref=sr_1_5?ie=UTF8&qid=1432655115&sr=8-5&keywords=Nordic+mythology