According to Danish Historian, Saxo Grammaticus, Book 1): Conquered, Hadding fled to Helsingland, where, while washing in the cold sea-water, he was attacked and cut down a beast of unknown kind with many blows, and having killed it, had it carried into camp. As he was exulting in this deed, a woman met him and addressed him with these words:
"Whether thou tread the fields afoot,
or spread canvas overseas,
thou shalt suffer the hate of the gods,
and through all the world shalt behold
the elements oppose thy purposes.
Afield thou shalt fall, on sea thou shalt be
an eternal tempest shall attend thy wandering,
nor shall rime ever quit thy sails;
nor shall thy roof-tree roof thee,
but if thou seek it, it shall fall smitten by the tempest; your herd shall perish from bitter cold.
All things shall be tainted,
and lament that thy lot is there.
Thou shalt be shunned a pestilence
nor shall any plague be fouler than thee.
Such chastisement doth the power of heaven mete out
for truly thy sacrilegious hands
have slain one of the dweller's above,
disguised in a shape that was not his:
thus here art thou,
the slayer of a benignant god!
When the sea receives thee,
the wrath of the winds shall be
loosed upon thy head."
And, when Hadding went back, he suffered all things after this fashion, and his coming brought chaos upon all peaceful places. When he was at sea, a mighty storm arose and destroyed his fleet: and when a shipwrecked man, wheresoever he sought shelter, there came a sudden downfall of that house. There was no remdy for his trouble, before he atoned by sacrifice for his crime, and was able to return into favour with heaven. For, in order to appease the gods, he sacrificed dusky victims to Frey. This manner of propitiation by sacrifice he repeated as an annual feast, and left posterity to follow. This rite the Swedes call Fröblod (the sacrifice or feast of Frey)."
In Book 1, Saxo gives us two accounts of Svipdag's death -- the one clearly converted into history, the other corresponding faithfully with the mythology. The former reports that Hadding conquered and slew Svipdag in a naval battle.The latter account is the killing of a strange beast by Hadding, in whom Freyja's husband might be recognized.From the continuation of the narrative, it appears that Hadding was unwilling to repent what he had done, although he was told that the one he had slain was a celestial being, and that he long refused to propitiate those gods whose sorrow and wrath he had awakened with the murder. Not until the woman's predictions were confirmed by terrible visitations does Hadding decide to reconcile with the powers in question. And he does so by instituting the annual sacrificial feast, called Frey's blot, thenceforth celebrated in honor of Frey.
That this god especially must be propitiated can, again, have no other reason than the fact that Frey was a nearer kinsman than any of the Aesir to the supernatural being, from whose slayer he (Frey) demanded a ransom. And as Saxo has already informed us that Svipdag perished in a "naval battle" with Hadding, all points to the conclusion that in the celestial person who was concealed in the guise of an animal and was slain in the water we discover Svipdag, Menglad-Freyja's husband.
Saxo does not tell us what animal guise it was. It must certainly have been a purely fabulous kind, since Saxo designates it as bellua inauditi generis, "beast of an unknown kind". An Anglo-Saxon record, designates it as wyrm and draca. That Svipdag, sentenced to wear this guise, kept himself in the water near the shore of a sea, follows from the fact that Hadding meets and kills him in the sea where he goes to bathe. Freyja, who sought her lost lover everywhere, also went in search for him to the realms of Ægir and Rán. There are reasons for assuming that she found him again, and, in spite of his transformation and the repulsive exterior he thereby got, she remained with him and sought to soothe his misery with her faithful love. One of Freyja's surnames shows that she at one time dwelt in the bosom of the sea. The name is Mardöll.
Another proof of this is the fragment preserved to our time of the myth concerning the conflict between Heimdall and Loki in regard to Brisingamen. This neck- and breast-ornament, celebrated in song both among the Teutonic tribes of England and those of Scandinavia, one of the most splendid works of the ancient artists, belonged to Freyja (Þrymskviða 13, Gylfaginning 35, Skáldskaparmál 28). She wore it when she was seeking Svipdag and found him beneath the waves of the sea; and the splendor which her Brisingamen diffused from the deep over the surface of the sea is the epic interpretation of the name Mardöll from mar, "sea," and döll,feminine of dallur (Old English deall), "glittering" (compare the names Heimdallur and Dellingur). Mardöll thus means "the one diffusing a glimmering in the sea". The fact that Brisingamen, together with its possessor, actually was for a time in Ægir's realm is proved by its epithet fagurt hafnýra, "the fair kidney of the sea," which occurs in a strophe of Ulf Uggason (Skáldskaparmál 23).
"Renowned defender [Heimdall] of the powers' way [Bifrost], kind of counsel, competes with Farbauti's terribly sly son at Singastein. Son of eight mothers plus one, mighty of mood, is first to get hold of the beautiful sea-kidney [Brisingamen]." (Faulkes tr.)
There was also a skerry, Vágasker, Singasteinn, on which Brisingamen lay and glittered, when Loki, clad in the guise of a seal, tried to steal it. Skáldskaparmál 15:"[Heimdall] is also the visitor to Vagasker and Singastein; when he contended with Loki for Brisingamen." But before he accomplished his purpose, there crept upon the skerry another seal, in whose looks -- persons in disguise were not able to change their eyes - the evil and cunning descendant of Farbauti must quickly have recognized his old opponent Heimdall. A conflict arose in regard to the possession of the ornament, and the brave son of the nine mothers became the victor and preserved the treasure for Asgard. Heimdall's and Loki's conflict in regard to Brisingamen has undoubtedly been an episode in the mythic account of Svipdag's last fortunes and Freyja's abode with him in the sea.
According to Saxo, at the time when he slays the monster, Hadding is wandering about as an exile in the wilderness. The unnamed woman, who after the murder had taken place puts herself in Hadding's way, informs him whom he has slain, and calls the wrath of the gods and the elements down upon him, must be Freyja herself, since she witnessed the deed and knew who was concealed in the guise of the dragon. So long as the latter lived Brisingamen surely had a faithful watcher, for it is the nature of a dragon to brood over the treasures he finds. After being slain and dragged on shore by Hadding, his "bed," the gold, lies exposed to view on Vagasker, and the glimmer of Brisingamen reaches Loki's eyes. While the woman, in despair on account of Svipdag's death, stands before Hadding and speaks to him, the ornament has no guardian, and Loki finds the occasion convenient for stealing it. But Heimdall, Hadding's protector, who in the mythology always keeps his eye on the acts of Loki and on his kinsmen hostile to the gods, is also present, and he too has seen Brisingamen.
Loki has assumed the guise of a seal, while the ornament lies on a rock in the sea, Vágasker, and it can cause no suspicion that a seal tries to find a resting-place there. Heimdall assumes the same guise, the seals fight on the rock, and Loki must retire with his errand unperformed. The rock is also called Singasteinn (Skáldskaparmál 15, 23), a name in which I see the Anglo-Saxon Sincastân, "the ornament rock". An echo of the combat about Brisingamen reappears in the Beowulf poem, where Heimdall (not Hamdir) appears under the name Hâma, and where it is said that "Hâma has brought to the weapon-glittering citadel (Asgard) Brosingamene," which was "the best ornament under heaven".
-William P Reaves