Æthelred I was King of Wessex from 865 until his death in 871. He was the fourth of five sons of King Æthelwulf of Wessex, four of whom in turn became king. Æthelred succeeded his elder brother Æthelb
Æthelred as depicted in the early fourteenth-century Genealogical Roll of the Kings of England
Charter S 332 dated 863 of King Æthelberht. Æthelred attests second from bottom on the left as "Æthelred fil[ius] reg[is]".
Charter S 338 dated 867. Æthelred, King of the West Saxons and the Men of Kent, grants Wighelm, priest, a seat in St Martin's Church, Canterbury, together with land. Most charters only survive as copies, and this is the only original of Æthelred to survive.
Silver penny of King Æthelberht of Wessex (Æthelred's predecessor)
Æthelwulf was King of Wessex from 839 to 858. In 825, his father, King Ecgberht, defeated King Beornwulf of Mercia, ending a long Mercian dominance over Anglo-Saxon England south of the Humber. Ecgber
Æthelred I of Wessex
…Æthel-ræd, lit. 'noble counsel'; 845/848 – Late April 871) was King of Wessex from 865 until his death in 871. He was the fourth of five sons of King Æthelwulf of Wessex, four of whom in turn became king. Æthelred succeeded his elder brother Æthelberht and was followed by his youngest brother, Alfred the Great. Æthelred…
Æthelwulf in the early fourteenth-century Genealogical Roll of the Kings of England
Depiction of Æthelwulf in the late-13th-century Genealogical Chronicle of the English Kings
Coin of King Æthelwulf: "EĐELVVLF REX", moneyer Manna, Canterbury
Charter S 316 dated 855, in which Æthelwulf granted land at Ulaham in Kent to his minister Ealdhere