Editing Æthelbald, King of Wessex (section)

== Background ==
When Æthelbald's grandfather [[Ecgberht, King of Wessex|Ecgberht]] became king of [[Wessex]] in 802, it would have seemed very unlikely that he would establish a lasting dynasty. For two hundred years, three families had fought for the West Saxon throne, and no son had followed his father as king. Ecgberht's nearest connection to a king of Wessex was as a great-great-grandson of Ingild, brother of King [[Ine of Wessex|Ine]] (688–726), but he was believed to be a [[Patrilineality|paternal descendant]] of [[Cerdic]], the founder of the West Saxon dynasty, which made him an [[ætheling]], a prince who had a legitimate claim to the throne. However, in the ninth and tenth centuries, Ecgberht's line controlled the kingdom, and all kings were sons of kings.{{sfnm|1a1=Abels|1y=2002|1p=85|2a1=Dumville|2y=1979 |2p=17|3a1=Stafford|3y=2001|3p=83}}

At the beginning of the ninth century, England was almost wholly under the control of the [[Anglo-Saxon]]s, and the Midland kingdom of [[Mercia]] dominated southern England. In 825, Ecgberht decisively defeated the Mercians at the [[Battle of Ellendun]], ending [[Mercian Supremacy|Mercian supremacy]]. The two kingdoms became allies, which was important in the resistance to [[Viking]] attacks.{{sfn|Keynes|1995|pp=28, 39–41}} In 835, the [[Isle of Sheppey]] in Kent was ravaged. In 836, Ecgberht was defeated by the Vikings at [[Carhampton]] in [[Somerset]], but in 838, he was victorious over an alliance of [[Cornishmen]] and Vikings at the [[Battle of Hingston Down]], reducing Cornwall to the status of a [[client kingdom]].{{sfnm|1a1=Stenton|1y=1971|1pp=235, 241|2a1=Charles-Edwards|2y=2013|2p=431|3a1=Edwards|3y=2004}} He died in the following year and was succeeded by his son Æthelwulf, who appointed his eldest son Æthelstan as sub-king of Kent, [[Kingdom of Essex|Essex]], [[Surrey]] and [[Kingdom of Sussex|Sussex]], in the same year.{{sfn|Nelson|2004}}