Valkyries are female spirits or demigoddesses in Norse mythology. The word valkyrie comes from old Norse valkyrja, and means "chooser of the slain." The valkyries are said to
…be the daughters of Odin. When there were battles in Midgard, the valkyries went there and decided what warriors should fall in the battle. They brought the fallen to Asgard where they became Einherjar and fought all day and feasted all night. The Einherjar were divided between Odin and Freyja. Odin's Einherjar lived in Valhall, Freyja's lived in Folkvang. Sometimes the valkyries are portrayed as riding winged horses, in other stories they can shapeshift into swans or ravens. In some stories valkyries marry human heroes. The valkyries often have names connected to battles, for example Sigurdrifa(victory-urger), Geirskogul(spear-shaker) and Skeggjold(axe time). ( Full Answer )