Battle of Mons Badonicus

At or around AD 500, (no reliable date available), a group of combatants who were either Romano-British, Celtic, or from both groups, inflicted a severe defeat on an invading Anglo-Saxon army at Mons Badonicus or Mynydd Baddon.

The location of this battle is controversial, as is the name of the Romano-British leader. Gildas, a near contemporary who states that in his essay, De Excidio Britonum or The Ruin of Britain that the battle occurred close to the year of his birth, does not name the leaders of either side, nor provides any information that helps identify its location.

A number of sites in Britain have been proposed in the last thousand years, distributed from near the border of present-day England and Scotland south to the edge of the island. All of these depend upon theories or speculations of scholars built from a poverty of evidence. Any suggested location must take into consideration these points:

1. The location of this battle probably lies on the frontier between the territories of the native British inhabitants and the Anglo-Saxon invaders; and
2. The Annales Cambriae, found in the Harleian recension of the Historia Brittonum, preserve an entry under the year 665 that records "The second battle of Mons Badonicus". While pointing to an engagement between two kingdoms of the seventh century, it is debatable which kingdoms this may be and whether this battle is recorded in other historical records of Britain or England.

The name of the specific participants is also debatable. The Historia Brittonum records traditions that name the Romano-British and Celtic leader as Arthur, while more recent scholarly speculation has claimed the Romano-British and Celtic leader was Ambrosius Aurelianus, and the Saxon leader to be Aelle of Sussex, King of the South Saxons.

However uncertain the place, date or participants of this battle may be, it clearly halted the Anglo-Saxon advance for a number of years. While the Anglo-Saxon Chronicle is silent about this battle, it clearly documents a gap of almost seventy years between two major Anglo-Saxon leaders, or Bretwaldas, in the fifth and sixth centuries. Procopius records a story, told to him by a member of a diplomatic delegation from the Franks, which included a group of Angles, which included the fact that a number of Anglo-Saxons and British found their island so crowded that they migrated into northern Gaul to find lands to live on. There are other tales from the mid-6th century about groups of Anglo-Saxons leaving Britain to settle across the English Channel, all of which point the existence of some kind of reversal in the fortunes of the invading Anglo-Saxons.

Archeological evidence collected from the cemeteries of the pagan Anglo-Saxon suggests a number of their settlements were abandoned and the frontier between the invaders and the native inhabitants pushed back sometime around AD 500. The Anglo-Saxons held the present-day counties of Kent, Sussex, Norfolk, Suffolk, and around the Humber; it is clear that the native British not only controlled everything west of a line drawn from the mouth of the Wiltshire Avon at Christchurch[?] north to the river Trent, then along that river to where it joined the Humber, and north along the river Derwent and then east to the North Sea, but also an enclave to the north and west of London, and south of Verulamium, that stretched west to join with the primary frontier. The Britons defending this pocket could securely move their troops along Watling Street to bring reinforcements to London or Verulamium, and thus keep the invaders divided into pockets south of the Weald, in eastern Kent, and in the lands surrounding the Wash.

If this theory is accurate, when Cuthwulf, an associate of Ceawlin of Wessex, defeated the British at Bedcanford and took the four towns of Limbury[?], Aylesbury, Benson[?], and Eynsham[?] later in the 6th century, then the British wedge between the Anglo-Saxon communities was broken, and the peace that followed this important battle came to an end.