After the Romans left, a number of tribes (stammen) from Europe invaded and settled in large numbers.
Two of these tribes were the Angles and the Saxons (German). These Anglo-Saxons soon invaded the south-east part of the country. They also tried to attack an invade the west, but their attempt was stopped by the legendary King Arthur. However, years later their way of life started to dominate in almost all of Britain.
The Anglo-Saxons didn't like big towns or cities. They were more effective on the countryside where they build self-sufficient villages, which formed the basis of English society for the next thousand or so years.
Britain experienced another wave of Germanic invasion in the 8th century. These Germanic invader were known as the Vikings and are from Scandinavia. They settled at the coast of Scotland and Ireland. Their conquest was stopped by King Alfred of the Saxon. Because of that loss, they could only settle at the coast or Scotland.
However, the cultural differences were so small between the Anglo-Saxons and the Danes that, at the end of the 8th century, they decided to join power and so united a kingdom with a Germanic culture. As a resul, the name England is used for the first time in 973! The name refers to the Anglos.
The invasion of the Anglo-Saxons and the Vikings https://www.youtube.com/watch?v=r9Tfbeqyu2U