410
The Roman legions left Britain.
450
Anglo-Saxon mercenaries began to take territory from the Britons.
450
450-600: The time of Arthur
Lots of luxury Mediterranean goods, such as wine and oil, were imported at Tintagel. The historian Gildas mentioned King Constantine of Dumnonia. Dumnonia was one of the most powerful kingdoms in Britain, with its centre in Cornwall and wealth based on the tin trade.
550
550-570: The making of Brittany
Britons living in Dumnonia were emigrating (moving) to Armorica. Armorica’s name was changed to Brittany, meaning ‘land of the Britons’ because so many people settled there.
550-600: Decline of the Kingdom of Dumnonia
Luxury imports into Tintagel stopped arriving and the power of Dumnonian kings declined. Over the next 200 years, Britons living in the southwest began to be described as 'Cornish'.
577
Battle of Deorham
Battle of Deorham (near Bristol). Victory for the Anglo-Saxons separated the Britons of the southwest from the Britons of Wales.
710
King Geraint, ruler of the western kingdom
The Cornish King Geraint was at war with Anglo-Saxon King Ine of Wessex. Both were claiming rule over Devon.
722
Battle of Hehil
A Cornish army defeated the Anglo-Saxons. The precise location of the battle is not certain but it took place ‘amongst the Cornish’.
807
Danish and Cornish alliance
Danish Vikings joined forces with the Cornish against the Anglo-Saxons.
825
Battle of Gafulford
Battle of Gafulford (possibly Galford in west Devon). The Anglo-Saxon King Egbert defeated a Cornish army.
838
Battle of Hingston Down
Battle of Hingston Down (possibly near Callington). A combined army of Cornish and Danish Viking forces was defeated by the Anglo-Saxon King Egbert.
875
King Doniert of Cornwall
Around this time, the Cornish King Doniert was drowned. His memorial stone can be found near St Cleer on Bodmin Moor.
936
Cornish border fixed
The English King Athelstan fixed the east bank of the River Tamar as the boundary between the Cornish and the English. This remains Cornwall’s boundary today.
1066
Normans and Bretons
The Norman Conquest of Britain. The Norman army included men from Brittany (Bretons), some speaking the Breton language, which was very similar to Cornish. Some land in Cornwall was granted to Bretons.