Anglo-Saxons
The Anglo-Saxons were a cultural group who inhabited Great Britain from the 5th century, and the direct ancestors of the majority of the modern British people. They comprise people from Germanic tribes who migrated to the island from continental Europe, their descendants, and indigenous British groups who adopted many aspects of Anglo-Saxon culture and language; the cultural foundations laid by the Anglo-Saxons are the foundation of the modern English legal system and of many aspects of English society; the modern English language owes over half its words – including the most common words of everyday speech – to the language of the Anglo-Saxons. Historically, the Anglo-Saxon period denotes the period in Britain between about 450 and 1066, after their initial settlement and up until the Norman conquest.
The early Anglo-Saxon period includes the creation of an English nation, with many of the aspects that survive today, including regional government of shires and hundreds. During this period, Christianity was established and there was a flowering of literature and language. Charters and law were also established. The term "Anglo-Saxon" is popularly used for the language that was spoken and written by the Anglo-Saxons in England and eastern Scotland between at least the mid-5th century and the mid-12th century. In scholarly use, it is more commonly called Old English.
Anglo-Saxon settlement of Britain
A major study in 2015 by Leslie et al. on the fine scale genetic structure of the British population revealed a rich and detailed pattern of genetic differentiation with remarkable concordance between genetic clusters and geography in the British Isles, showing clear signals of historical demographic events. Based on two separate analyses, the study found clear evidence in modern England of the Anglo-Saxon migration and identified the regions not carrying genetic material from these migrations, but with each analysis limiting the proportion of Saxon ancestry and clearly excluding the possibility of long-term Saxon replacement. The proportion of Saxon ancestry in Central/Southern England was found to be very likely under 50%, and most likely in the range 10%-40%. Additionally, in the 'non-Saxon' parts of the UK there was found to exist genetically differentiated subgroups rather than a general 'Celtic' population.