Editing Æthelberht, King of Wessex (section)

== Background ==
When Æthelberht's grandfather [[Ecgberht, King of Wessex|Ecgberht]] became king of [[Wessex]] in 802, it must have seemed very unlikely to contemporaries 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 previous 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 paternal descendant of [[Cerdic]], the founder of the West Saxon dynasty. This made Ecgberht an [[ætheling]] – a prince who had a legitimate claim to the throne. But in the ninth and tenth centuries, descent from Cerdic was no longer sufficient to make a man an ætheling: 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. The Midland kingdom of [[Mercia]] dominated southern England, but their supremacy came to an end in 825 when they were decisively defeated by Ecgberht at the [[Battle of Ellendun]]. The two kingdoms became allies, which was important in the resistance to [[Viking]] attacks.{{sfn|Keynes|1995|pp=28, 39–41}} In the same year Ecgberht sent his son [[Æthelwulf]] to conquer the Mercian sub-kingdom of [[Kingdom of Kent|Kent]] (the area of the [[Kent|modern county]] plus [[Kingdom of Essex|Essex]], [[Surrey]] and [[Kingdom of Sussex|Sussex]]) and appointed him sub-king.{{sfn|Nelson|2004}} In 835 the [[Isle of Sheppey]] was ravaged by Vikings and in the following year they defeated Ecgberht 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}} He died in 839 and was succeeded by Æthelwulf,{{sfn|Nelson|2004}} who appointed his eldest son [[Æthelstan of Kent|Æthelstan]] as sub-king of Kent. Æthelwulf and Ecgberht may not have intended a permanent union between Wessex and Kent as they both appointed sons as sub-kings and charters in Wessex were attested (witnessed) by West Saxon magnates, while Kentish charters were witnessed by the Kentish elite; both kings kept overall control and the sub-kings were not allowed to issue their own coinage.{{sfn|Abels|1998|p=31}}

Viking raids increased in the early 840s on both sides of the [[English Channel]], and in 843 Æthelwulf was defeated by the companies of 35 Danish ships at Carhampton.{{sfn|Nelson|2004}} In 850 Æthelstan defeated a Danish fleet off [[Sandwich, Kent|Sandwich]] in the first recorded naval battle in English history.{{sfn|Stenton|1971|p=244}} In 851 Æthelwulf and his second son [[Æthelbald, King of Wessex|Æthelbald]] defeated the Vikings at the [[Battle of Aclea]] and, according to the ''[[Anglo-Saxon Chronicle]]'', "there made the greatest slaughter of a heathen raiding-army that we have heard tell of up to this present day, and there took the victory".{{sfn|Swanton|2000|p=64}}