Saxon invasions of Wales

The Timeline of conflict in Anglo-Saxon Britain is concerned with the period of history from just before the departure of the Roman Army, in the 4th century, to just after the Norman Conquest in the 11th century.

The information is mainly derived from annals and the Venerable Bede. The dates, particularly from the fourth to the late sixth centuries, have very few contemporary sources and are largely later constructions by medieval chroniclers. The historian Diana Greenway described one such 12th century chronicler, Henry of Huntingdon, as a 'weaver' compiler of history, and the archaeologist Martin Welch described the Anglo-Saxon Chronicle as "a product of the West Saxon court... concerned with glorifying the royal ancestry of Alfred the Great. Manipulation of royal genealogies, in this and other sources, to enhance the claims of present rulers was common. Literary formulas associated with original myths are a common feature of earlier entries." Although the timeline uses the annals for this period of history, information provided by these sources can be problematic, particularly with the earlier dates.

Constructing a chronology of the early Anglo-Saxon period, and how the Anglo-Saxons took over land in Britain from Romano-Britons (Celtic-speakers, Latin-speakers, or both), is highly complex. The limitations of source material place restrictions on just how accurate any chronology can be. As an example, the following table shows how much variation there is between historians on just one date, the Battle of Badon:

Much of the dating of the period comes from Bede (672/673–735), who in his Ecclesiastical History of the English People, tried to compute dates for events in early Anglo-Saxon history. Although primarily writing about church history, Bede is seen as Britain's first true historian, in that he cited his references and listed events according to dates rather than regnal lists. So we know that he relied heavily on De Excidio et Conquestu Britanniae by Gildas, a sixth-century cleric, for his early dates and historians have found Gildas unreliable where dates were concerned. Bede's work was widely read among the literate in the Anglo-Saxon kingdoms, and his dates were used by the monks who compiled the various Anglo-Saxon Chronicles from the late ninth century onwards.

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