This is one of those old stories from the past whose author is unknown and likely is a composite of a large variety of stories told for decades before being written down. I like these enormously.
From the back page:
“Based on oral tales that originated in historical events in tenth-century Iceland, these two sagas follow the fate of a powerful Viking family across two generations, from its early Norwegian ancestry through fierce battles to defend its honor. Gisli Sursson’s Saga is a story of forbidden love and divided loyanties, in which the heroic Gisli vows to avenge the murder of his ‘sworn brother’ and sets in motion a chain of bloody events that culminate in tragedy. The Saga of the People of Eyri continues the story of Snorri, a cunning leader of the next generation, who uses his intellect to restore social order. Blending gripping narrative, humour, the supernatural and shrewd observation, these tales reveal the richness of the saga tradition and present a vivid record of a society moving from ruthless individualism to a Christian ethic od reconciliation and order.”
One more example of the facts that human nature has not changed very much in thousands of years and that the old stories can still captivate.