Æthelbald of Mercia

Æthelbald (also spelled Ethelbald, or Aethelbald) (died 757) was the King of Mercia, in what is now the English Midlands from 716 until he was killed in 757. Æthelbald was the son of Alweo and thus a grandson of Eowa, who was the brother of Penda. Æthelbald came to the throne after the death of his cousin, King Ceolred, who had driven him into exile. During his long reign, Mercia became the dominant kingdom of the Anglo-Saxons, and recovered the position of pre-eminence it had enjoyed during the strong reigns of Mercian kings Penda and Wulfhere between about 628 and 675.

When Æthelbald came to the throne, both Wessex and Kent were ruled by stronger kings, but within fifteen years the contemporary chronicler Bede describes Æthelbald as ruling all England south of the river Humber. The Anglo-Saxon Chronicle does not list Æthelbald as a bretwalda, or "Ruler of Britain", though this may be due to the West Saxon origin of the Chronicle.

St. Boniface wrote to Æthelbald in about 745, reproving him for various dissolute and irreligious acts. The subsequent 747 council of Clovesho and a charter Æthelbald issued at Gumley in 749—which freed the church from some of its obligations—may have been responses to Boniface's letter. Æthelbald was killed in 757 by his bodyguards. He was succeeded briefly by Beornred, of whom little is known, but within a year, Offa, the grandson of Æthelbald's cousin Eanwulf, had seized the throne, possibly after a brief civil war. Under Offa, Mercia entered its most prosperous and influential period.

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