I've never read Shakespeare's MacBeth, though I don't know if that was an advantage or a disadvantage while reading "King Thereafter," by Dorothy Dunnett.
In Mrs. Dunnett's well-researched historical novel, she theorized that MacBeth and Thorfinn were not two separate people, but were the same historical figure. Here is a time line of that era featuring other historical figures in "King Thereafter," such as King Canute and King Malcolm.
The first character introduced in the novel was Thorkel Amundason, Thorfinn's foster father and a presence in Thorfinn's adult life as well. An excerpt from "King Thereafter" featuring Thorkel (beginning with the first line in Chapter One) can be found here.
A bit of the tale about the power struggle between the Earls of Orkney when Thorfinn started to consolidate his power base can be found here.
The prevalent characteristic about Thorfinn (MacBeth) was his approach to life and his style as king -- it was a chess match where he was several moves ahead of his opponents. This tendency was revealed early; "Here was a youth, it seemed to indicate, ready to fall in with the wishes of others. Sulien could not tell why, therefore, he became seized with the certainty that this proposal of Alfgar's (Note: Lady Godiva's son) was what Thorfinn had intended to do all along." (Page 30) If events did not turn out as anticipated, MacBeth's mind was agile enough to adjust to circumstances, even in the end.
MacBeth is no longer just a character in a Shakespeare play to me after reading "King Thereafter."
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