Tolkien derived the characters, stories, places, and languages of Middle-earth from many sources. Among these are Norse mythology, seen in his Dwarves, Wargs, Trolls, Beorn and the barrow-wight, places such as Mirkwood, characters including the Wizards Gandalf and Saruman and the Dark Lords Morgoth and Sauron derived from the Norse god Odin, magical artefacts like the One Ring and Aragorn's sword Andúril, and the quality that Tolkien called "Northern courage". The powerful Valar, too, somewhat resemble the pantheon of Norse gods, the Æsir.