Brythons

State · 439–1235 CE · at its largest around 439 CE

The Celtic Britons who held much of western and northern Britain after the end of Roman rule, organised in many small kingdoms and speaking Brittonic languages.

On its lands while it lasted

Anglo-Saxon settlement of Britain (c. 450 CE): Angles, Saxons and Jutes from northern Germany and Denmark settled in lowland Britain, laying the foundations of England and the English language.
Canterbury (c. 490 CE): Capital of Kingdom of Kent (490–762).
Winchester (c. 534 CE): Capital of Kingdom of Wessex (534–927), Kingdom of England (936–1100).
Lincoln (c. 534 CE): Capital of Kingdom of Lindsey (534–625).
Worcester (c. 577 CE): Capital of Hwicce (577–627).
Carlisle (c. 592 CE): Capital of Kingdom of Rheged (592–646).
Edinburgh (601 CE): Capital of Kingdom of Scotland (1452–1608).
Staffordshire Hoard (c. 650 CE): The largest hoard of Anglo-Saxon gold and silver metalwork ever found, with more than 3,500 pieces, mostly fittings from weapons. Buried in the 7th century in Mercia, it was found near Hammerwich in 2009.
Bede (c. 673 CE – 735 CE): English monk at Jarrow whose Ecclesiastical History of the English People earned him the title father of English history.
Truro (c. 710 CE): Capital of Cornwall (710–946).
Viking raid on Lindisfarne (793 CE): Viking raid on the monastery of Lindisfarne in Northumbria, conventionally taken as the beginning of the Viking Age.
William the Conqueror (c. 1028 CE – 1087 CE): Duke of Normandy who conquered England in 1066 and became its first Norman king.
Battle of Hastings (1066 CE): William, Duke of Normandy, defeated and killed King Harold II, beginning the Norman conquest of England.
University of Oxford (c. 1096 CE): Teaching existed at Oxford by 1096, making it the oldest university in the English-speaking world. It grew rapidly after Henry II barred English students from the University of Paris in 1167.
Magna Carta (1215 CE): Charter agreed by King John at Runnymede that limited royal power and became a foundation of constitutional law in the English-speaking world.