In 793 CE Viking raiders from Norway, Denmark and Sweden attacked a string of Monasteries along the east coast of England and Scotland.
From 865 the Vikings saw Britain as suitable for colonisation. Larger fleets steered across the North Sea to British shores bringing armies and settlers.
In 865 the Great Heathen Army numbering just a few thousand landed in Norfolk.
In 866 the city of York in Northumbria fell to the Norsemen followed by Mercian Nottingham a year later. In 869 The Danes marched on East Anglia. In 871 fresh reinforcements arrived from Scandinavia in the form of the Great Summer Army.
Now the Viking forces felt confident they could take on Wessex however they were defeated by Alfred who would later be known as Alfred the Great.
The Viking army stayed at London during 871 and 872 before marching north to Northumbria to quell a rebellion.
In 874 The Viking Army conquered Mercia and drove it’s king into exile.
The conquered Northumbrian and Mercian territory was divided amongst the Viking warriors to farm and settle.
Following the battle of Edrington in 878 where Alfred once again defeated the Norse army led by Guthrum, negotiations were entered into and a treaty drawn up. The treaty divided the land between the Anglo Saxons in the South and the Viking territory’s in the East and North known as the Danelaw.
The boundary was described as along the Thames, then up the River Lea to its source. Straight up to Bedford, then along the River Ouse and up Watling Street.
This great boundary can still be seen in the names of towns and villages and can be argued to be the origin of the North South divide.
To consolidate their territory and protect against Anglo-Saxon invasion. The Norsemen fortified five towns known as the ‘Five Boroughs’.
Map showing the boundary of the Danelaw as agreed between the Treaty of Alfred of Wessex and Guthrum in around 890 CE.
The map also shows the density of Viking settlement names ending in 'thorpe', 'toft' and 'by'.
The five fortified towns of the Viking Boroughs are marked as is Eoeorwic (York) and Lunden (London) which was reclaimed by the Saxons in 886 CE.