Æthelred succeeded to the throne on Æthelberht's death in 865, and he married Wulfthryth at an unknown date. West Saxon kings' wives had a low status in the ninth century and very little is known about them. They were not usually given the title of regina (queen), an omission which Alfred the Great justified on the ground of the misconduct of a queen at the beginning of the ninth century. The name of Æthelred's wife is only known because she was recorded as a witness to one charter, S 340 of 868, where she is shown as Wulfthryth regina, suggesting that she had a higher status than other kings' wives. The only other ninth century king's wife known to have been given the title was Æthelwulf's second wife, Judith of Flanders, a great-granddaughter of Charlemagne. Wulfthryth and Æthelred had two known sons, Æthelhelm and Æthelwold. She might have been Mercian or a daughter of Wulfhere, Ealdorman of Wiltshire, who forfeited his lands after being charged with deserting King Alfred for the Danes in about 878, perhaps because he attempted to secure Viking support for his elder grandson Æthelhelm's claim to the throne against Alfred.