A couple years ago, I read in The Letters of J.R.R. Tolkien that Tolkien had written poem that attempted "to unify the lays about the Volsungs from the Elder Edda," written in the Old Norse eight-line stanzaic metre. Having read William Morris's brilliant epic poem Sigurd the Volsung, I was delighted to think that Tolkien's poem might still exist, but pessimistic that it might ever see publication. Happily, Christopher Tolkien has found and edited the work and released it as The Legend of Sigurd and Gudrun. Rather than a single poem, the work is composed of two poems.
The first recounts the life of Sigurd, the greatest hero of Norse legend, describing his slaying of the dragon Fafnir and his acquiring Andvari's gold. Later, his romance with the beautiful valkyrie Brynhild, his alliance with the Niflung, and his tragic end. The second recounts the life of Gudrun following Sigurd's death. Sigurd had been enchanted by Gudrun's mother, causing him to fall in love with Gudrun and breaking his vow to marry Brynhild. With the death of Sigrun and Brynhild, Gudrun lived in sorrow, watching her family destroyed, and finally cast herself into the sea to drown.
The death of Gudrun in Tolkien's version is different from most treatments of the story. For example, in the Magnusson-Morris translation, Gudrun is washed ashore and eventually marries for a third time, living in sorrow and weaving a tapestry depicting the life of Sigurd. Tolkien's version is, however, not unique. William Morris's later work also ends with her death by drowning.
Tolkien's poetry, faithful to the Old Norse metre, is beautifully archaic and stirring, but nonetheless clear and intelligible to the modern reader. The story's unity seems to owe much to William Morris's work. In his letters, Tolkien notes having read and been influenced by Morris's romances, though he does not mention Sigurd the Volsung. It is unlikely that he did not read it, though.
Much of Tolkien's posthumous work has been of interest only to his die-hard readers. Happily, this work and his previously published work The Children of Hurin are more accessible and in line with the works that have made him famous. For anyone who appreciated The Lord of the Rings, these recent publications will be an exciting adventure back into Middle Earth and the legends upon which it was conceived.
A good bit has been said about Tolkien's appropriation of names from the Eddas for The Lord of the Rings, particularly, Gandalf and Frodo; however, I have not read commentary that has drawn parallels between the life of Sigurd and Aragorn, Brynhild and Arwen, and Gudrun and Eowyn -- parallels that are of much greater interest.
In the Eddas, Sigurd falls in love with Brynhild the valkyrie. Before marrying her he sets off to earn her love and journeys to the house of the Niblungs. There, he leads them to greatness, but is enchanted by Gudrun's mother, causing him to fall in love with Gudrun. Similarly, in The Lord of the Rings, Aragorn falls in love with Arwen the elf, but before marrying her, heads off to join the House of Theoden (the Riders of Rohan), also leading them to greatness. Furthermore, just as the Niblungs defend themselves against the Budlungs in a bloody siege in Atli's hall, so too do the Riders of Rohan defend themselves against the forces of Sauruman at Helm's Deep. Finally, in a looser parallel, just as Atli, King of the Budlungs, is married to Gudrun of the Niblungs, so too is Grima Wormtongue (Sauruman's lieutenant) seeking to marry Eowyn, daughter of Theoden.
There are, of course, dissimilarities in the story. There is no enchantress in Rohan to cause Aragorn to fall in love with Eowyn as Sigurd fell in love with Gudrun, betraying Brynhild, but the attraction between Aragorn and Eowyn surely threatens to betray Arwen. The most significant dissimilarity lies in the victory of the Riders of Rohan at Helm's Deep. Where the Niblungs are defeated by the Budlungs, the Riders of Rohan are saved by what Tolkien describes in an essay as a "eucatastrophe." Just as the besieged Riders of Rohan are preparing to end their lives in a paradigmatically Norse fashion, with an honorable and glorious, but completely hopeless attack on the enemy, Gandalf arrives with a contingent of Riders to rescue the beseiged -- a "good castastrophe."
Clearly, Tolkien is indebted to the Lay of the Niblungs, but in his hands the story is transformed into one in which hope is triumphant, but while the valor characteristic of the ancient Norse remains undiminished.