King Olaf of Norway made preparations to convert Iceland. To this end he sent Thangbrand, son of Count Willibald of Saxony, on a mission to Iceland.
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At Stafafell a farmer named Thorkel challenged Thangbrand to a duel. Thangbrand accepted the challenge and went to battle using a crucifix for a shield. Victory went to Thangbrand, and he killed Thorkel.
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Frightened at the Christians' success, the heathens at Kerlingardale hired a sorcerer named Hedin to kill their leader Thangbrand. ...At the time Thangbrand was riding westwards, and the ground suddenly opened up beneath his horse. The horse disappeared into the earth, but Thangbrand miraculously pulled himself to safety.
Thangbrand's companion Gudleif searched out Hedin the sorcerer and killed him with a spear.
.... Fljotshlid, where they met great opposition from Vetrlidi the Poet, so they killed him.
At Grimsness Thorvald the Ailing had gathered a large band of Icelanders against the missionaries.... Thangbrand threw a spear through Thorvald, then Gudleif cut off his arm, and Thorvald died.
......(Thangbrand returns to Norway)...
Thangbrand's account so angered the king that Olaf had all Icelanders in Norway thrown into dungeons. He threatened to have them all put to death, but was dissuaded...