King of Wessex (858–860), eldest surviving son of Æthelwulf, who rebelled against his father and scandalously married his father's young widow before his short reign ended.
Æthelbald was king of Wessex from 858 to 860, the eldest surviving son of Æthelwulf and an elder brother of Alfred the Great. He is remembered chiefly for the manner of his coming to power: while his father was on pilgrimage to Rome in 855–856, Æthelbald led a conspiracy to seize the throne, and on Æthelwulf's return the kingdom was divided between them to avoid war.
On his father's death in 858 Æthelbald took the whole of Wessex, and promptly scandalised the Church by marrying Judith, his father's young Frankish widow — a union condemned as contrary to canon law. His reign lasted barely two years before his death in 860, when the crown passed to his brother Æthelberht.
Æthelbald was born about 831, one of the elder sons of King Æthelwulf. He grew up as a prince of the dominant English kingdom and, as his father aged, came to expect the succession. His impatience for it, and perhaps fear that Æthelwulf's pilgrimage and Frankish marriage might reorder the inheritance, drove him into rebellion.
Æthelbald is a dimly recorded figure, seen mostly through two controversial acts — his rebellion and his marriage — that earned him the disapproval of the churchmen who wrote the sources. From them he emerges as ambitious, headstrong, and heedless of both filial duty and canon law: a prince who would not wait for a crown, and a king who took his father's widow in defiance of the Church.
Whether this is the whole man is impossible to know; his reign was too short, and the record too thin and hostile, to reveal much else. He was clearly forceful and self-willed, and his revolt showed the dangerous ambition that could grip a royal heir. But he also proved willing, in 856, to accept a compromise rather than fight his own father to the death — so that even his rebellion stopped short of the worst. He remains the wayward eldest brother in the story of Æthelwulf's remarkable sons.
The defining episode of Æthelbald's life came during his father's absence in Rome. With the support of some leading men, Æthelbald plotted to prevent Æthelwulf's return to power. The old king, coming home in 856, chose not to fight: rather than tear Wessex apart, he agreed to a partition, leaving Æthelbald the western, senior portion of the kingdom.
When Æthelwulf died in 858, Æthelbald ruled the whole of Wessex. His marriage to Judith, his father's widow — a girl of perhaps fourteen, and a great-granddaughter of Charlemagne — was denounced by the Church as incestuous and unlawful, and appears to have been dissolved. His brief reign left little other mark before his early death.
Æthelbald died on 20 December 860, after a reign of about two years, and was buried at Sherborne. Having no heir to succeed him, he was followed by his brother Æthelberht, who reunited the western kingdom with the south-east he already ruled.
Æthelbald is remembered as the least edifying of the sons of Æthelwulf — the rebel prince and scandalous king whose short reign is a cautionary episode between his father's careful rule and the reunification under his brothers. His death without heirs cleared the way for the orderly succession of Æthelberht, Æthelred, and finally Alfred, under whom the House of Wessex would meet and master the Viking storm.