King Ethelred I was a son of Ethelwulf of Wessex and was born around 837 AD. He succeeded his brother, Ethelbert of Wessex, as King of Wessex in about 865. He had two sons, Ethelwald being the elder. Ethelred I was not able to control the increasing Danish raids which devastated England. On January 4, 871 at the Battle of Reading Ethelred defeated a Danish invasion army. However, he was killed at the Battle of Merton on April 23, 871 and is buried at Wimborne in Dorset. Following his death, he was popularly regarded as a saint, but never canonised. He was succeeded by his brother, King Alfred the Great.
Ethelred, the younger son of Edgar, became king at the age of seven following the murder of his half-brother Edward II in 978 at Corfe Castle, Dorset, by Edward's own supporters.
For the rest of Ethelred's rule (reigned 978-1016), his brother became a posthumous rallying point for political unrest; a hostile Church transformed Edward into a royal martyr.
Not being an able soldier, Ethelred defended the country against increasingly rapacious Viking raids from the 980s onwards by diplomatic alliance with the duke of Normandy in 991 (he later married the duke's daughter Emma) and by buying off renewed attacks by the Danes with money levied through a tax called the Danegeld.
Born into the royal house of Wessex, which was at that time the effective ruler of all the Anglo-Saxons, Ethelred was a direct descendant of Alfred the Great and the son of King Edgar, who had ruled a united and peaceful England for 16 years.
From the time of Ethelred's accession at the age of 9 or 10, his reign was tragically marred by the treason and revolt of his leading thegns (noblemen).
Ethelred and Edmund joined forces against the invader early in 1016 at London.