I am thinking specifically of this part (taken from wikipedia):
“Following his defeat, Edmund was forced to sign a treaty with Canute. By this treaty, all of England except Wessex would be controlled by Canute and when one of the kings should die the other would take all of England, that king's son being the heir to the throne.”
Was this a common solution for solving disputes at the time? That when one person died, the other would get what they were fighting over? Could there be a religious aspect to this where they essentially let god decide?
I suppose that the conditions mentioned in the treaty could be indeed not impossible in the 11th century Northern Europe, and the main impetus of such conditions should be primarily sought in the political atmosphere of the English nobility at that time, not in the contemporary religiosity, though it was as certainly suggested by the scribe of the Eulogy for Queen Emma (Encomium Emmae Reginae) as following:
'But yet God, who remembered His own ancient teaching, according to which a kingdom divided against itself cannot long stand, soon afterwards, pitying the realm of the English, took away Eadmund from the body, lest it should chance that if both survived neither should rule securely, and that the kingdom should be continually wasted by renewed conflict (Encomium Emmae Reginae, II-14, in: Campbell (ed. & trans.) 1998: 30f.).
Alternative interpretation could be that magnates formerly divided in both sides agreed to camouflage it as actually concluded after Edmund's death. The text of the treaty itself was not extant, and neither of variants of Anglo-Saxon Chronicles (D, E, F), written almost contemporary, mention the existence of the succession clause in question in their narratives.
My main reason of favoring the former interpretation (mentioned first in my post) is the existence of the closest parallel(s), under very similar political surroundings. It was allegedly concluded between Cnut's son, Harthacnut of England-Denmark on one side and Magnus the Good of Norway on another in ca. 1037/38, after a skirmish, on the succession of Denmark. While some historians had also doubt the authenticity of this peace treaty, several (almost mutually independent) historical writings from the 12th and 13th century Scandinavia record that they concluded a treaty in similar conditions. The following is an excerpt taken from the oldest of such kinds of texts, Roskilde Chronicle (ca. 1140):
'Then, Harthacnut and Magnus, King of Norway, concluded the following agreement and confirmed it by taking an oath upon the reliquary: who of two would outlive another should take the kingdom of the diseased, and inherit the two kingdoms as if they would be his own hereditary posession (Chronicon Roskildense, Chap. 9, in: Gertz (cra.) 1917: 22. Clumsy translation is done by mine)'.
Norwegian monk Theodoricus adds furthers on the surroundings of this agreement:
'Whereupon leading men, seeing that two kings, still immature, could easily be swayed in any direction, and that they themselves more likely bear the blame for anything the kings might do amiss, fell back on the more sensible plan of negotiating peace (Chapter 22, translation is taken from McDougall(s) (trans.) 1998: 34).
These descriptions indeed resemble strikingly with those surrounding the alleged treaty between Cnut and Edmund: Young rulers, the possibly strong voices of their political advisors those who not really wish to keep the wars any further, and the pledge taken on the reliquary. I assume the peace negotiation itself and the following pledge in both cases were carefully directed by the advisors of both parties to promote the 'official' reconciliation of their rulers, still not so stubborn willed to act on their own.
On the other hand, Williams points out another possible parallel of this treaty, the compromise of 957 concluded between Eadwig and his brother Edger (Williams 2003: 146), though I think the Danish example is more closer to the situations surrounding Cnut and Edmund in 1016.
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