Vikings, Wessex, & The Unification

The first recorded Viking attack in Britain was in 793 at Lindisfarne monastery as given by the Anglo-Saxon Chronicle. However, by then the Vikings were almost certainly well established in Orkney and Shetland, and it is probable that many other non-recorded raids occurred before this. Records do show the first Viking attack on Iona taking place in 794.

The arrival of the Vikings, in particular the Danish Great Heathen Army, upset the political and social geography of Britain and Ireland. Alfred the Great's victory at Edington in 878 stemmed the Danish attack; however, by then Northumbria had devolved into Bernicia and a Viking kingdom, Mercia had been split down the middle, and East Anglia ceased to exist as an Anglo-Saxon polity. The Vikings had similar effects on the various kingdoms of the Irish, Scots, Picts and (to a lesser extent) Welsh. Certainly in North Britain the Vikings were one reason behind the formation of the Kingdom of Alba, which eventually evolved into Scotland.

The conquest of Northumbria, north-western Mercia and East Anglia by the Danes led to widespread Danish settlement in these areas. In the early tenth century the Norwegian rulers of Dublin took over the Danish kingdom of York. Danish and Norwegian settlement made enough of an impact to leave significant traces in the English language; many fundamental words in modern English are derived from Old Norse, though of the 100 most used words in English the vast majority are Old English in origin. Similarly, many place-names in areas of Danish and Norwegian settlement have Scandinavian roots.

By the end of Alfred's reign in 899 he was the only remaining English king, having reduced Mercia to a dependency of Wessex, governed by his son-in-law Ealdorman Aethelred. Cornwall (Kernow) was subject to West Saxon dominance, and the Welsh kingdoms recognised Alfred as their overlord.