Earlier blog posts described how Sigurd wakened, wooed, and won the Valkyrie Brynhild. They lay together, and he swore to love her faithfully and return soon from his adventures to marry her. As a pledge of his love, he left with her the cursed ring Andvaranaut which he had taken from Fafnir’s hoard. Then he rode on to the castle of King Gjuki, where the birds whose words had guided him to Brynhild had promised him that he’d find his fortune.
King Gjuki saw that his guest was strong and bold, and also possessed of dragon-treasure, and he made Sigurd very welcome indeed. So did his queen Grimhild and their sons Gunnar, Hogni, and Guttorm. But the king's daughter Gudrun fell deeply and hopelessly in love with their guest; hopelessly, because he spoke often and fondly of his beloved and betrothed, Brynhild.
Grimhild saw her daughter’s grief and took matters into her own hands. She was wise in the magic arts, and she made a potion and dropped it into Sigurd’s drinking horn. Now Brynhild had taught Sigurd ale-runes to guard against potions and poisons, but Sigurd had never been overcautious, and he thought he was among friends. He drank trustingly, and all his memories of Brynhild vanished as though they had never been.
Then there was nothing to distract him from Gudrun’s beauty and her high heart, and when Gjuki offered Sigurd his daughter’s hand and a high place in the kingdom, Sigurd accepted delightedly. In time Gudrun bore him a son, Sigmund.
Sigurd did great deeds in Gjuki’s wars and was well beloved throughout the land, most of all by his brothers the king’s sons. But the eldest of those brothers, Gunnar, was weary of single life and wanted a wife. His mother Grimhild urged him to wed Brynhild, the loveliest and bravest woman she had heard of, and to get Sigurd’s help in wooing her.
(Had Grimhild forgotten that Brynhild had drunk no draught of forgetfulness? Was she plotting Sigurd’s death in jealousy over his fame? Was she simply caught up in Andvari’s curse? Nobody knows.)
Now after Sigurd’s departure Brynhild had remained in the castle on the Hindfell, and the wall of enchanted flames still blazed about her. When the brothers rode to the castle, Gunnar steeled himself to ride through the flames, but his horse shied away, and Gunnar didn’t attempt a passage on foot. Sigurd’s horse refused to bear Gunnar anywhere. At last the brothers used a magic Grimhild had taught them to exchange shapes. Sigurd’s horse still knew him when he wore Gunnar’s form, and it carried him through the fire to Brynhild. And even when Sigurd stood gazing at his old love, Grimhild’s spell still bound him so that he did not recall ever having seen her before.
Brynhild was immortal and wise in many things, but in this she understood less than the horse. She thought that her wooer was indeed Gunnar, and at first she was loath to accept his offer. But he urged that she had promised to marry any man who passed through the flames. At last she accepted him—perhaps for the sake of her oath, perhaps because she believed the ordeal by fire proved his courage, perhaps because Sigurd was long away and the daughter he had gotten on her, Aslaug, was growing up fatherless. They plighted troth and lay in one bed, but Sigurd, meaning to keep faith with Gudrun and not to betray Gunnar, laid his sword in the bed between them. When he rode away in the morning, bidding her follow him when she could, she gave him a ring. Yes, that ring, Andvaranaut the cursed.