Stefnir Thorgilsson was one of the first Christian missionaries among the Icelanders at the end of the 10th century. He was born in Iceland. King Olaf Tryggvason, king of Norway (r. 997-1000) ordered him to return to his homeland in order to proselytize among the Icelanders. He destroyed a number of heathen temples and idols, for which he was expelled from the island.
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Stefnir Thorgilsson Wikipedia(Text) CC BY-SA