This is an incomplete list of the wars and battles between the Anglo-Saxons who later formed into the Kingdom of England and the Britons (the pre-existing Brythonic population of Britain south of the Antonine Wall who came to be known later by the English as the Welsh), as well as the conflicts between the English and Welsh in subsequent centuries. The list begins after the Adventus Saxonum in c. AD 446 (when the Anglo-Saxons are said to have arrived in Britain) to the late Middle Ages when England annexed the whole of Wales in 1535. The list is not exhaustive but seeks to note the significant campaigns and the major battles.

5th century

Pagan Germanic tribes who have colonized parts of the eastern and southern coasts of Britannia attack the Britons, whom the Anglo-Saxons dub Wīelisċ (“Welsh; Briton; Roman; Celt”), in a series of immigrations and coordinated uprisings. Additional reinforcements from Old Saxony, Angeln, Flanders and Jutland make landings and mostly through treaty occupy large areas of eastern and south eastern Britain.

Arthurian Battles listed in the Historia Brittonum.

6th century

Pagan Anglo-Saxon tribes conquer southern Britain capturing London, Colchester, Silchester, Chichester, Winchester, Grantchester, Leicester, Gloucester, Cirencester, Bath, York, Lincoln and Canterbury among other places. Later in the century Angles defeat the northern Britons and colonize the north eastern coast.

7th century

The Anglo-Saxons consolidate their hold on southern and eastern Britain. The Mercian Angles made substantial gains in central Britain (today known as the English Midlands). Cambria is cut off from the Britons of the north west and the south west. The Anglo-Saxons convert to Christianity by the middle of the century. The last serious attempts by the Britons to reclaim Britain fail.

8th century

The British territories in the south west (now Cornwall and much of Devon) defend themselves and push the English back. The borders of modern Wales are broadly defined as Mercian expansion grinds to a halt.

9th century

During the first half of the century a reinvigorated Mercia almost conquers the rest of Wales. At the end of the century Viking raids on England divert some attention from the British.

[Map of the extent of Hywel Dda's power {{legend|#aaeeff|Deheubarth, Hywel Dda's principality}}{{legend|#ffb380|Combine to form Morgannwg|undefined | upload.wikimedia.org/wikipedia/commons/2/27/Wales///900-950///%28Hywel///the///Good%29.svg]

10th century

A period of relative peace as Hywel Dda comes to dominate most of Wales and forms an alliance with Wessex against the Vikings who have destroyed the power of Mercia.

11th century

A united kingdom of England is formed. The Welsh are united for a while under Gruffudd ap Llywelyn but he is killed in renewed infighting before the Norman Conquest of England. The new Norman masters of England launch the Norman invasion of Wales and ravage some parts of the Welsh kingdoms.

12th century

Civil wars amongst the Norman overlords of England allow the Welsh kingdoms space to consolidate their positions. The end of the century sees a resurgent Gwynedd expand at the expense of her neighbours.

13th century

The primacy of Gwynedd continues up to the middle of the century when a "Principality of Wales" is proclaimed by Llywelyn Fawr. After a period of tumult following the death of Llywelyn's successor as prince, Dafydd ap Llywelyn, Dafydd's nephew Llywelyn ap Gruffudd emerges as a major force in Welsh politics, assuming the title of prince of Wales in 1258 and establishing his authority in Powys and Deheubarth. Llywelyn's death in 1282, and the subsequent capture and execution of his brother and successor, Dafydd ap Gruffudd, in 1283 signify the end of Welsh independence. The end of the century sees the annexation of Wales and the Edwardian Settlement.

[Wales 1234 (Marchia Wallie and Pura Wallia) {{legend|#87de87|Pura Wallia (independent Wales)}}{{legend|#aaeeff|Lands gained by Llywelyn the Great in 1234}}{{legend|#ffb380|Marchia Wallia (lands ruled by the Marcher barons)|undefined | upload.wikimedia.org/wikipedia/commons/2/20/Wales///1234///%28Marchia///Wallie///and///Pura///Wallia%29.svg]

14th century

A period of relative stability under English rule, punctuated by two significant revolts.

15th century

Civil conflict in England and the deposition of Richard II are the background for the national uprising led by Owain Glyndŵr who is successful in liberating all of Wales from the English. He is eventually defeated and English control of Wales is reimposed.