9th Century.
c800 AD.
Earliest date by which Welsh cleric Nennius could have begun "Historia Brittonum", which he describes as a "heap of all I found".
806 AD.
Danes burn Iona, killing 68 monks.
825 AD.
The Mercians' defeat at the hands of Egbert of Wessex at the battle of Ellendun meant that supremacy passed to Wessex.
835 AD.
First recorded Viking raid.
842 AD.
Danes raid London, Rochester (Kent), and Southampton.
851 AD.
First recorded naval battle in English history, off Sandwich, Kent: Kentish ships defeat Danish fleet. Danes spent first winter in England, at Thanet, Kent.
855 AD.
Ethelbald was the eldest son of Ethelwulf. He took over his father's authority in 855 and married Judith, daughter of Charles the Bald, king of the Franks, who was also his stepmother. Edmund becomes King of the East Angles.
860 AD.
Ethelbert was Ethelbald's brother. He ruled from 860 to 866.
865 AD.
"Great Army" of Danes - led by King Ivar "The Boneless" and Halfdan - land in East Anglia.
866-867 AD.
Danes take York, defeat Northumbrians and impose puppet king on them. Northumbria and Mercia buy peace from Danes.
869 AD.
20th November, Danes under Ivar defeat and kill St. Edmund, King of East Anglia, at Hoxne, Suffolk. St. Edmund becomes the Patron Saint of England.
871 AD.
Wessex army under King Ethelred and brother Alfred defeats Danes. After losing later battles, Wessex buys peace from Danes. Ethelred dies, succeeded by Alfred.
877-878 AD.
Southern Danish army under Guthrum conquers most of Wessex. Alfred retreats to Athelney, Summerset, builds fort and begins guerrilla warfare. At the battle of Edington (Wilts) - 878 AD., Alfred defeats Danes under Guthrum, Danes make peace; Guthrum is baptized, with Alfred as godfather. Danish army settles in East Anglia where Guthrum becomes king.
879 AD.
A large part of Mercia was taken over by the Vikings, forming part of 'Danelaw'.
886 AD.
Alfred frees London from the Danes. He and "all English councillors" make a treaty with Guthrum: Eastern England between the rivers Thames and Tees is declared Danish Territory (later "Danelaw").
893-896 AD.
The Anglo-Saxon Chronicles is compiled in English. New Danish army under Hastein invades from France, joined by Danes of York and East Anglia. Alfred builds battle fleet to defeat the Danes.
899 AD.
Alfred dies, succeeded by his son Edward, 'the Elder".