"They say that a king known as Holgi, after whom Halogaland is named, was Thorgerd Holgabrud's father. Sacrifices were offered to them both, and Holgi's mound was raised with alternately a layer of gold or silver-this was the money offered in sacrifice-and a layer of earth and stone." (Faulkes translation)
"How then is Hakon's worship to be explained? The reason is that he traced his descent from the ancient kings of Halogaland. When his ancestors migrated to the south, they must have brought their family cult with them. The persistent nature of family worship is shown by the fact that we find the family settled in the neighbourhood of the Throndheim Fjord at least a century before Hakon acquired the government of Norway." (The Ancient Teutonic Priesthood)
Chadwick adds a footnote that "it is curious that in Eyvindr's poem (Haleygiatal), of which only some fragments remain, Hakon's genealogy is traced, not to Holgi and Thorgerdr, but to Othin and Skadi. The introduction of Othin's name may be due in part to the influence of Ynglingatal, but it is probable also that Hakon may have wished to conciliate popular opinion by tracing his descent from the generally accepted deities. Skadi, a goddess of Lappish character but accepted in the Northern pantheon, has been cleverly substituted for the hated Thorgerdr." Chadwick also points out that although "Thorgerdr is never mentioned as a member of the divine community either in the mythological poems or in Gylfaginning, nor does she stand in any kind of relationship to the rest of the gods." and that "Her cult formed no part of the orthodox religion of the North." nevertheless she concedes that "In the North the clearest case of a tribal cult is that of Thorgerdr Holgabrudr." Chadwick is of the opinion that "Thorgerdr seems to bear a distinctly Lappish character, e.g. in her use of the bow and in the practice of magical arts." I am inclined to agree with her on this point and it is quite possible that Her cult was imported from the far north into Norway and thus is not entirely indigenous. She certainly appears to be a much wilder and archaic deity than those of the Eddas although She is referred to in Gylfaginning.
Apart from Earl Haakon other prominent followers of Thorgerdr were Ketill Haengr and Grimkell:
"She seems to have been one of the powers revered by the Halogalander Ketill Haengr, who, like other members of his family, did not worship the generally recognised gods. She is also said to have been worshipped by an Icelandic settler named Grimkell, who came from Orkadal, a district to the south of the Throndheim Fjord." (Chadwick)
"If Helgi were the mythical founder of Halogaland, this would explain Thorgerd's name 'Bride of Helgi', since she could become the wife of each ruler of the kingdom in turn. The idea of the guardian goddess welcoming the king in death was essentially an aristocratic concept, just as was that of kings and leaders granted entry to Valhalla, and this is one important aspect of the goddess in the Viking Age."
"Thereupon the earl went up on the island of Primsigned, and away into a forest, and fell on his knees and prayed, looking northward. And in his prayer he called upon his patron goddess, Thorgerd Holgabrud. But she would not hear his prayer and was wroth. He offered to make her many a sacrifice, but she refused each one, and he thought his case desperate. In the end he offered her a human sacrifice, but she would not have it. At last he offered her his own seven-year old son; and that she accepted. Then the earl put the boy in the hands of his slave Skopti, and Skopti slew him." (Hollander translation)
"And right soon the weather began to thicken in the north and clouds covered the sky and the daylight waned. Next came flashes of lightning and thunder, and with them a violent shower. The Jomsvikings had to fight facing into the storm, and the squall was so heavy that they could hardly stand up against it.
"Havard the Hewing was the first to see Thorgerd Holgabrud in the fleet of Earl Hakon, and then many a second-sighted man saw her. And when the squall abated a little they saw that an arrow flew from every finger of the ogress, and each arrow felled a man. They told Sigvaldi, and he said: 'It seems we are not fighting men alone, but still it behoves us to do our best.'
"And when the storm lessened a bit Earl Hakon again invoked Thorgerd and said that he had done his utmost." (Hollander)
"Meanwhile, Earl Hakon was attending a feast at Gudbrand's home. During the night, Hrapp the Killer went to their temple. Inside it, he saw the statue of Thorgerd Holgi's-Bride enthroned, massive as a fully-grown man; there was a huge gold bracelet on her arm, and a linen hood over her head. Hrapp stripped off the hood and the bracelet. Then he noticed Thor in his chariot, and took from him another gold bracelet. He took a third bracelet from Irpa. He dragged all three of the idols outside and stripped them of their vestments; then he set fire to the temple and burned it down." (Chapter 88, Magnusson and Palsson translation)
(This was a clear act of desecration and not just theft). Haakon comments:
"A man must have fired the temple and dragged the gods out. But the gods are in no haste to take vengeance; the man who did this will be driven out of Valhalla for ever."(Magnusson and Palsson)
"They set forth along a certain path to the wood, and thence by a little bypath into the wood, till they came where a ride lay before them, and a house standing in it with a stake fence round it. Right fair was that house, and gold and silver was run into the carvings thereof. They went into the house, Hacon and Sigmund, and a few men with them. Therein were a great many gods. There were many glass roof-lights in the house, so that there was no shadow anywhere. There was a woman in the house over against the door, right fairly decked she was. The Earl cast him down at her feet, and there he lay long, and when he rose up he told Sigmund that they should bring her some offering and lay the silver thereof on the stool before her." (Chapter 23, translation by F. York Powell)
"In the Saga of Olaf Tryyvason in Flateyjarbok (I, 326:408), Olaf is said to take Thorgerd's image from the temple at Trondheim, strip it of its fine robe and gold and silver ornaments, drag it along at his horse's tail and finally break it up and burn it along with the image of Freyr……..When he destroyed her image, Olaf declared that now she had lost Hakon, her husband, 'who was very dear to her', and added that the chiefs of the land had been loyal to her in turn, and had given her high praise." (The Lost Beliefs of Northern Europe)