The Anglo Saxons
The origins of the Anglo Saxons is really a mish mash of many tribes including not just the Angles and Saxons but also the Jutes, Franks, Frisians and many others whose names have been long lost to history. We dont know the real reason they came but its likely that a mixture of the collapse of Roman dominance in the west , environmental factors such as climate change and pressures from the east pushing tribes ever further west, all culminated in the eventual settlement of various Germanic tribes in Britannia. There is much debate as if this was a full scale invasion or a peaceful settlement but the reality is that is was likely a mixture of both over time and different areas of Britain.
This ebb and flow of tide of migration, military conquest, settlement and interaction took over 200 years to solidify into a number of Kingdoms called the heptarchy. Even then these Kingdoms fought each other plus the Romano British by then known as the Welsh for many centuries to come as well as other foreign invaders such as the Vikings. The period we call the Dark Ages was one that was defined by these conflicts, often on a small scale involving local disputes over boarders but at times these would amply into fighting in wider theatres of war. However there was also peace amongst these times as the nation that would become England also managed to become extremely wealthy and productive.
How were these people different ?
Despite the claims of some false narratives the Germanic tribes that came to Britain were not that genetically different from their Celtic cousins who already lived here. Where they did differ was in language (Brythonic a form of welsh and also Latin were the main languages of the Romano British) and cultural heritage. By the time of the migration period Britain was mostly Celtic Christian whilst the tribes that came were pagans worshiping Woden, Thunnor and Ing Frey. Over time the language of these tribes know known as Anglo Saxon or Old English took dominance, and nearly all place names in England have AS language origins. This total replacement of language, place names, and culture throughout England in the 5th to 7th Century's shows the extent to which this change took place. There is much debate as to how this happened but looking at other examples in the world of such cultural changes it is impossible to see how this could have taken place completely peacefully!
The Anglo Saxons also differed in their basic way of life. The Romano British had villas, towns and even cities. Whilst they obviously had agriculture they also centered on a very Romanised way of life with stone buildings, roads and other infrastructure though much of this was in decline by the time of the migrations. The Anglo Saxons however lived in generally small rural communities in wooden buildings based around farming and self sustenance. Their loyalty was to their tribe and their local Ealdorman or King who in turn protected them with his warrior elite. During these times many skills or items of technology such as the potting wheel were lost and for years ,many thought this meant they were a primitive people. However delicate and intricate finds such as those at Sutton Hoo and the Staffordshire Hoard show they were also extremely skilled craftsmen. And poetic works such as Beowulf and the Battle of Maldon show they had a rich cultural heritage of word and music. Unfortunately much of this has been lost to time as little has survived in the ground and many written sources have been destroyed.