And the challenges still remained: While Alfred had forced the Danes into a treaty in 886 the land they inhabited still remained outside of the control of Wessex. Nor had the Vikings stopped their raiding merely because turn of the century was almost at hand.
In 911 A.D. Æthelred died; his wife Ethelfleda (who has come down in history as "The Lady of Mercia") administered Mercia until her own death in 918 A.D. As part of Æthelred's death, Wessex inherited the lands around London and Oxford. Both Edward and Ethelfleda began building forts (burhs) based on the initial strategy of their father Alfred and as they began leapfrogging eastward. Besides building there was fighting; by 918 A.D. all the Danelaw had submitted to Edward. Ethelfleda had died as well in 918 A.D. and the Mercian territory was now brought fully under the control of Wessex.
Meanwhile, in the North a new threat re-appeared: The Vikings of Jarvik (York)
To go forward, we have to go back a bit: As you may recall, during the Invasion of the Great Heathen Army in Alfred the Great's day, Northumbria was invaded by the Danes. The city of York (Norse: Jorvik) was captured and administered as a kingdom until 901 A.D. when the above mentioned Æthelwold briefly ruled until his death in battle and replacement by another Viking King. An uneasy series of submission and invasions to place as the King of York would submit to the Anglo-Saxon King, then turn around and invade. Thus the threat from the north continued for years after the Danelaw had been integrated under the ruling house of Wessex.
Edward The Elder died in 924 A.D. and his son Æthelstan took the throne after some years of dispute. He conquered the kingdom of York in 927 A.D. As part of this conquest, the kingdoms of Scotland, Strathclyde, Bernicia, and part of Wales submitted to him, making Æthelstan the first ruler of all the English lands. The submission lasted until 934 A.D., when Scotland broke the treaty. Æthelstan invaded Scotland in return. The invasion in return called forth an alliance of Scotland, Strathclyde, and Hiberno-Norse Vikings from the Kingdom Dublin. In 937 A.D. all sides met at the Battle of Brunanburh.
Brunanburh is attested to by multiple sources in Anglo Saxon, Welsh, Scottish, Norman, and Irish sources. The date of the battle is guessed to be in October, but we do not know that - nor do we fully know where the battle itself took place. We do know that the battle was an all day affair and terribly costly. We do know that it inspired a poem in the Anglo-Saxon Chronicle. And we do know, after the terrible slaughter, the Anglo-Saxon army held the field and chased the survivors away.
The outcome of Brunanburh to history is disputed. Æthelstan would die within two years and the Kingdoms of Strathclyde and Scotland would remain independent. The Hiberno-Norse were perhaps less of an immediate threat, but that did not end the Danish or Norwegian Viking threat. However, it did preserve the Anglo-Saxon portion of the kingdom as a whole unit; one can imagine that if Æthelstan had lost, there was a very real chance the kingdom could have dissolved back into some level of its component units. The unity of Anglo-Saxon England was still a relatively new things, and beneath the surface the old independence of Mercia and Danelaw undoubtedly lurked.
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Brooke, Christopher: From Alfred to Henry III 871-1272. Norton Library: USA, 1961.
Trevelyan, G.M.: History of England Volume 1: From the Earliest Times to the Reformation. Anchor Books: USA, 1953
Nicolle, David: Arthur And The Anglo-Saxon Wars. Osprey Publishing: Hong Kong, 1984
Heath, Ian: The Vikings. Osprey Publishing: Hong Kong, 1985
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