Aethelred, the son of
Osburga, was born in about 840.
In 868 AD Aethelred backed his brother-in-law, Burghred of Mercia, when Mercia was subject to Danish attack. In 871 Wessex itself was invaded by the Danes and Aethelred fought alongside his brother, Alfred, to drive them out.
King Aethelred died April 23 871 at Merton after being wounded by the Vikings, and is buried in Wimborne Minster. He was succeed by his brother, Alfred.
His son, Aethelwald, was expelled from Wessex and took refuge in Northumbria where he became a King at York.