Anglo-Saxon Invasion

When the Roman left Britain, this resulted in Picks and Scots crossing Hadrian's Wall and attacking the Britons. That in turn resuled  in King Vortigern asking the Romans for protection which was  provided for a short  time. in 418 A. D., the roman again left and this again resulted in the Britons being attacked. Vortigern now obtained help from three Germanic  tribes of Engels, Kimbern and Saxons.
what he did not know was that all three of them had confederated into the one very powerful tribe. Each tribe operated under the commands of its own nobility, but always under the banner of the Saxons! this story continue to the end of reign of King Alfred the Great.