Aethelbald’s Wars (733–750)PRINCIPAL COMBATANTS: Mercia vs. Wessex and Northumbria
PRINCIPAL THEATER(S): England
DECLARATION: Not known; probably none
MAJOR ISSUES AND OBJECTIVES: The Mercian king Aethelbald and his cousin-successor, Offa, invaded Wessex and Northumbria with the purpose of establishing Mercian dominance of Anglo-Saxon England, thereby effecting the first real unification of England.
OUTCOME: Wessex was successfully invaded in 733 and Northumbria in 744, ultimately resulting in the unification of much of England under Aethelbald and his successor, Offa.
APPROXIMATE MAXIMUM NUMBER OF MEN UNDER ARMS:Unknown
TREATIES: No surviving documents
Aethelbald (r. 716–757) was king of Mercia, the richest and most powerful kingdom of Anglo-Saxon England. He set out to parlay this advantage into out-and-out political supremacy among the kings and disparate kingdoms of Britain. His first step, in 733, was to invade Wessex in the south of England, seizing it from the Britons. He next invaded Northumbria in 744 and again in 749, causing great hardship and devastation in the region. During this period he also asserted dominance over kings of the regions bordering Wales by assisting them in defendingagainst Welsh border incursions.
By the end of the 740s Aethelbald’s conquests had earned him the title “king of Britain,” and he was recognized as an equal by no less a figure than Charlemagne (c. 742–814). Historians generally concede that he effected the first meaningful unification of England. Nevertheless, his reign following the conquest of Wessex and Northumbria was marked by an intense civil war, and Aethelbald himself was assassinated by his bodyguard in 757. His cousin Offa (r. 757–796), who had participated in Aethelbald’s campaigns only to oppose him in the civil war, succeeded him to the Mercian throne.
See also OFFA’S WARS (771–796).
Further reading: Albany F. Major, Early Wars of Wessex (Poole, U.K.: Blandford Press, 1978); David A. E. Peteret, ed., Anglo-Saxon History: Basic Readings (New York: Garland, 2000).