Editing Æthelflæd (section)

==Background==
Mercia was the dominant kingdom in southern England in the eighth century and maintained its position until it suffered a decisive defeat by Wessex at the [[Battle of Ellendun]] in 825. Thereafter the two kingdoms became allies, which was to be an important factor in English resistance to the Vikings.{{sfn|Keynes | Lapidge|1983|pp=11–12}}

In 865 the Viking [[Great Heathen Army]] landed in [[Kingdom of East Anglia|East Anglia]] and used this as a starting point for an invasion. The East Anglians were forced to buy peace and the following year the Vikings invaded [[Northumbria]], where they appointed [[Ecgberht I of Northumbria|a puppet king]] in 867. They then moved on Mercia, where they spent the winter of 867–868. King [[Burgred]] of Mercia was joined by King [[Æthelred of Wessex]] and his brother, the future King Alfred, for a combined attack on the Vikings, who refused an engagement; in the end the Mercians bought peace with them. The following year, the Vikings conquered East Anglia.{{sfn|Stenton|1971|pp=246–248}} In 874 the Vikings expelled King Burgred and [[Ceolwulf II of Mercia|Ceolwulf]] became the last King of Mercia with their support. In 877 the Vikings partitioned Mercia, taking the eastern regions for themselves and allowing Ceolwulf to keep the western ones. He was described by the ''[[Anglo-Saxon Chronicle]]'' as "a foolish king's [[thegn]]" who was a puppet of the Vikings. The historian [[Ann Williams (historian)|Ann Williams]] regards this view as partial and distorted, that he was accepted as a true king by the Mercians and by King Alfred.{{sfnm|1a1=Williams|1y=1991b|2a1=Williams|2y=1991c}} The situation was transformed the following year when Alfred won a decisive victory over the Danes at the [[Battle of Edington]].{{sfn|Stenton|1971|p=255}}

Ceolwulf is not recorded after 879. His successor as the ruler of the English western half of Mercia, Æthelflæd's husband [[Æthelred, Lord of the Mercians|Æthelred]], is first seen in 881 when, according to the historian of medieval Wales, [[Thomas Charles-Edwards]], he led an unsuccessful Mercian invasion of the north Welsh [[Kingdom of Gwynedd]]. In 883, he made a grant with the consent of King Alfred, thus acknowledging Alfred's lordship. In 886 Alfred occupied the Mercian town of [[Anglo-Saxon London|London]], which had been in Viking hands. He then received the submission of all English not under Viking control and handed control of London over to Æthelred. In the 890s, Æthelred and [[Edward the Elder|Edward]], Alfred's son and future successor, fought off more Viking attacks.{{sfnm|1a1=Costambeys|1y=2004b|2a1=Charles-Edwards|2y=2013|2pp=490–491}} Alfred died in 899 and Edward's claim to the throne was disputed by [[Æthelwold ætheling|Æthelwold]], son of Alfred's elder brother. Æthelwold joined forces with the Vikings when he was unable to get sufficient support in Wessex, and his rebellion only ended with his death in battle in December 902.{{sfn|Miller|2011}}