The title of Bretwalda was one perhaps used by some of the kings of the kingdoms of England (the so-called Anglo-Saxon heptarchy) in the second half of the first millennium AD. Such a king was considered to be the overlord of several Anglo-Saxon kingdoms. This was not a title as such and was certainly not inherited or even maintained within a kingdom. Most Bretwaldas had to fight for overlordship; violence should never be overlooked in Anglo-Saxon politics.

The word is derived from the Anglo-Saxon Bretanwealda, "Lord of Britain" — referring to the Saxon king's claim to overlordship of the Britons, or perhaps "wide-ruling".

Bede does not use the title Bretwalda, as is commonly thought, for the first seven of the following kings. Bretwalda is an Old English word and Bede was writing in Latin. Bede attributes these kings with holding imperium. The Anglo-Saxon Chronicle uses Bede as its source for the first seven kings and adds later kings of Wessex, primarily due to it being of West Saxon origin. The term Bretwalda is a problematic one and is best left in favour of the word 'overlord' which better describes the relationship the king held with the various other kings and peoples of Britain.

A Bretwalda, if we are to use the term, exercised overlordship over several other kingdoms, and often these were furthered through marriage. A clear sign of overlordship was a 'Bretwalda' granting land with charters in another kingdom. When a Bretwalda ruled over a larger kingdom, such as a Mercian ruler over East Anglia, the relationship would have been more equal than in the case of a larger kingdom ruling over a smaller one, as in the case of Mercia and Hwicce.

• Ælle of Sussex (477–circa 514)
• Ceawlin of Wessex (560–591)
• Ethelbert of Kent (591–616)
• Raedwald of East Anglia (616–627)
• Edwin of Deira (627–632)
• Oswald of Bernicia (633–641)
• Oswiu of Northumbria (641–670)
• Ethelbald of Mercia (circa 735–757)
• Offa of Mercia (757–796)
• Egbert of Wessex (829–839)
• Ethelwulf of Wessex (839–855)
• Ethelbald of Wessex (855–860)
• Ethelbert of Wessex (860–866)
• Ethelred of Wessex (866–871)
• Alfred the Great of Wessex (871–899)

The original lists of Bretwaldas did not contain the kings Ethelbald and Offa of Mercia, but in all probability they were considered overlords in their time and are included above. Bede does not record Ethelbald or Offa as Ethelbald lived at the same time as Bede (Bede commented little on current affairs in his Historia Ecclesiastica gentis Anglorum) and Offa was after Bede's time (Bede died in 735).

There is little evidence of the extent to which the title 'Bretwalda' was used in the Anglo-Saxon period, but it gradually fell into disuse around or after the Danish invasion of the 860s and 870s. During this invasion and settlement the old powerful kingdoms of Northumbria, East Anglia, Essex and much of Mercia were defeated by the Vikings. Wessex held out under King Alfred, who made closer links between Wessex and Mercia, an important move towards an English kingdom, though such a development should never be seen as inevitable. Alfred was called 'King of the Anglo-Saxons' in charters, while his grandson Athelstan was first called King of the English. It was not until Edgar, however, that the English kingdom finally became firmly established.

See also

• Mythical pre-Saxon King of the Britons
• List of monarchs of England
• List of British monarchs