Editing Cnut (section)

=== Siege of London ===
[[File:EdmundIronside Canutethe Dane1.jpg|upright=1.8|thumb|Medieval illumination depicting Kings [[Edmund Ironside]] (left) and Cnut (right), from the ''[[Chronica Majora]]'' written and illustrated by [[Matthew Paris]].]]

Cnut returned southward, and the Danish army evidently divided, some dealing with Edmund, who had broken out of London before Cnut's encirclement of the city was complete, and had gone to gather an army in [[Wessex]], the traditional heartland of the English monarchy. Part of the Danish army besieged London, constructing dikes on the northern and southern flanks and a channel dug across the banks of the Thames to the south of the city, enabling their longships to cut off communications up-river.

There was a battle fought at [[Penselwood]] in [[Somerset]] – with a hill in [[Selwood Forest]] as the likely location{{sfn|Lawson|2004|p=28}} – and [[Battle of Sherston|a subsequent battle]] at [[Sherston, Wiltshire|Sherston]], in [[Wiltshire]], which was fought over two days but left neither side victorious.<ref>''Anglo-Saxon Chronicles'', pp. 148–50</ref>

Edmund was able to temporarily relieve London, driving the enemy away and defeating them after crossing the Thames at [[Brentford]].{{sfn|Lawson|2004|p=28}} Suffering heavy losses, he withdrew to Wessex to gather fresh troops, and the Danes again brought London under siege, but after another unsuccessful assault they withdrew into Kent under attack by the English, with a battle fought at [[Otford]]. At this point Eadric Streona went over to King Edmund,<ref>''Anglo-Saxon Chronicles'', pp. 150–51</ref> and Cnut set sail northwards across the Thames estuary to [[Essex]], and went from the landing of the ships up the [[River Orwell]] to ravage Mercia.{{sfn|Lawson|2004|p=28}}