Anglo-Saxon invasion
Who were the Anglo-Saxons?
The Angle, Saxon, and Jute tribes who invaded Britain in the 5th and 6th centuries are known as the Anglo-Saxons. They left their homelands in northern Germany, Denmark and northern Holland and rowed across the North Sea in wooden boats.
Why did they come?
Historians are not sure why the Anglo-Saxons came to Britain. It may have been because their land often flooded and it was difficult to grow crops, so they were looking for new places to settle down and farm. Some sources say that Saxon warriors were invited to come to England.
Where did they settle?
The Anglo-Saxons took control of most of Britain, although they never conquered Scotland, Wales and Cornwall. They divided the country into kingdoms, each with its own royal family. The stronger kingdoms often took control of the weaker kingdoms. By around AD 600 the five main Anglo-Saxon kingdoms were Northumbria, Mercia, Wessex, Kent and Anglia.
http://www.bbc.co.uk/schools/anglosaxons/invasion/index.shtml