History of Anglo-Saxon England
English unification (10th century)
When Æthelred died in 911, his widow administered the Mercian province with the title "Lady of the Mercians". As commander of the Mercian army she worked with her brother, Edward the Elder, to win back the Mercian lands that were under Danish control. Edward and his successors expanded Alfred's network of fortified burhs, a key element of their strategy, enabling them to go on the offensive. Edward recaptured Essex in 913. Edward's son, Æthelstan, annexed Northumbria and forced the kings of Wales to submit; at the Battle of Brunanburh in 937, he defeated an alliance of the Scots, Danes, and Vikings to become King of all England.
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