Narrowing down where "King" Arthur was

Narrowing down where "(King) Arthur" was.
In this article we try to show how we narrow down where Arthur was from the whole universe or world to either Kent (and/or Essex/London?) or Wessex? We survey all the possible areas suggested by the source texts and by medieval and modern scholars. (Note that this is only a first provisional edition and there are still lots of bits to add in.)

Ursa / Arcturus / Draco ruled out:
Uther Pendragon and Arthur have been connected with Draco and Ursa major/minor or Arcturus, and the Round Table with the globe, and the 12 battles with the zodiac. However, I think that Arthur and his battles are implied in the source texts to have been real happenings on Earth rather than mythical happenings in the heavens. Arthur's name is not definitely agreed to mean "bear" or to be connected with Arcturus. It is said that Uther as Arthur's father only comes from a misinterpretation of "Mabuter" in the HB. So we can rule out Arthur's battles having been in Space or the heavens or sky.

Arctic/Polar ruled out:
Uther and Arthur have been connected with Draco and Ursa major/minor or Arcturus. However, Arthur is British/Welsh and/or in "(the island of) Britain" in early traditional sources, he is not placed in the Arctic or North pole. Britain qualifies as being Arctic and/or near Arcturus. So we can rule out the Arctic as Arthur's main realm.

Sarmatia / homeland of the Alans ruled out:
Some modern scholars connect Arthur with Lucius Artorius Castus and the Sarmatians/Alans/Narts. There might be a connection of Alannus (= Mannus) in the HRB with Avalon? However, early traditional sources like the HB & HRB have Arthur as British/Welsh and/or in "(the island of) Britain" not in Sarmatia or the homeland of the Alans. Also Arthur is sometime between the 300s and 700s in traditional sources, while LAC was in the 100s or 200s before then. So although Arthur might possibly be connected with Sarmatian/Alan Roman soldiers in Britain, we can rule out Sarmatia or the homeland of the Alans as Arthur's main historical realm.

Jerusalem/Calvary ruled out:
The HB VR says Arthur visited Jerusalem. However, early traditional sources like the HB & HRB have Arthur as British/Welsh and/or in Britain. So we can rule out Jerusalem as Arthur's main realm. "Jerusalem" in Arthurian traditional sources might be Cursalen or Verulam and/or the city of the legion and not the real Jerusalem?

Rome ruled out:
Arthur is supposed to have beaten the Western or Eastern Roman emperor Lucius Tiberius in battle in the HRB. Arthur is said to have become emperor of Rome. However, early traditional sources like the HB & the HRB have Arthur as British/Welsh and/or in "(the island of) Britain". Lucius Tiberius is only a [consul?] not an emperor in some other sources. The HRB otherwise has Leo as emperor in Arthur's time. So we can rule our Rome and the Western/Eastern Roman empire as Arthur's main realm. The city of the legion or "Caerleon" was also called "2nd Rome" (ref 24 kings & 33 cities document).

Sicily/Messina/Etna ruled out:
Sicily features in some early medieval Arthurian traditions. Avalon has been supposed to be in Sicily. Mt Etna and Messina have been connected with Morgana le Fay, and Etna has been connected with the burial place of Arthur. However, early traditional sources like the HB & the HRB have Arthur as British/Welsh and/or in Britain. So we can rule out Sicily as Arthur's main realm.
The Arthurian Sicily traditions might possibly only be from the Normans in Sicily, or the Crusades (of Richard Lionheart), or from correspondence of Britons/Britain with the Brutti in Calabria?
"Etna" and "Messena" in Arthurian sources might be figurative for Dover (where there is a place named Edinburgh Hill) and the strait(s) of Dover? Sigar "Sicily" is connected with Dobar in the 8 labours of Turein.

Saracen or Moorish ruled out:
There was a Saracen among the knights of the Round Table, and Aglovale had a half-Moorish son.
However they only first appear in 13th century sources, and there is otherwise no evidence in early Arthurian traditional source texts for Arthur having being in Saracen or Morrish lands.

"Estrusia" (Etruria/Tuscany/Tyrrhenia?) ruled out:
Estrusia is mentioned among Arthur's dominions in the HRB, though it is implied to have been under a duke not Arthur. However traditional sources like the HB & HRB imply Arthur was British/Welsh and/or was in "(the island of) Britain".

Africa, Grecia, Spain, Parthia, Media, Libya, Phrygia, Iturea, Egypt, Babylon, Bithynia, Syria, Boeotia, Crete ruled out:
These areas were under emperor Lucius Tiberius not Arthur in the HRB. Arthur beat Lucius Tiberius so he maybe could be said to have become overlord of these areas. But in traditional sources like the HB & HRB Arthur is associated with the Britons/Welsh and/or was in "(the island of) Britain" (and/or Loegria/England). I thought I saw the Sowdon of Babylon mentioned in an Arthurian source, but on searching it seems it is in a story set in Charlemagne's time not Arthur's.
So we can rule out these areas as Arthur's main realm.

Iceland ruled out:
Arthur is said to have conquered Iceland in the HRB. There were also Culdees in Iceland. Waddell reckoned the Edda was British. However, in early traditional sources Arthur is British/Welsh/English and/or was in "(the island of) Britain" and Loegria/England. Iceland was the realm of Malvasius not of Arthur (HRB). So we can rule out Iceland as Arthur's main realm.

Norway/Loclyn, Sweden, Gothland ruled out:
Arthur conquered "Norway" and "Gothland" in the HRB. There is a king Arthus in the Swedish kinglist. However, in early traditional sources Arthur is British/Welsh/English and/or was in "(the island of) Britain" and Loegria/England (refs HB, HRB). "Riculf" of "Norway" in the HRB might be Reculver/Regulbium or Norfolk/Norwich or Northumbria or North Wales or Normandy or Rico/Ridoc/Oxford?
Norway was the realm of Lot not of Arthur (HRB).
Gothland was the realm of Doldavius not of Arthur (HRB).
Arthus in the Swedish king list is in the 600s after the time of Arthur (before/until Ida). Arthus may match Cadwallon or Cadwaladr as a 2nd Arthur.
So we can rule out Norway or Sweden as Arthur's main realm.

"Dacia" or Denmark ruled out:
Arthur is said to have conquered "Dacia" or "Denmark" in the HRB. However, in early traditional sources Arthur is British/Welsh/English and/or was in "(the island of) Britain" and Loegria/England (refs HB, HRB).
"Dacia" was the realm of Aschillius not of Arthur (HRB).
So we can rule out Denmark or Dacia as Arthur's main realm.

Ireland ruled out:
There are only one or two modern theories that do have Arthur as Irish and/or in Ireland. Arthur is said to have invaded Ireland in 519. Morholt was an Irish knight in Tristan. However, traditional sources like the HB & HRB have Arthur as British and/or in Britain, not Irish and/or in Ireland. Ireland was the realm of Guillamurius or Iseult not of Arthur (HRB).
So we can rule out Ireland as Arthur's main realm.
"Cold snakeless Ireland" in the Wonders of Britain may be connected with either Caldicot "cold isle cottage", snakeless Thanet (Richard of Cirencester), Lucius Tiberius/Hiberius (HRB), and/or Hisberna (8 labours of Turein).

France/Gaul/Gaunnes/Gallia/Celts / Aquitaine/Allobroges / Brittany/Armorica/Letavia/Broceliande ruled out:
Arthurian places that have been supposed to be located in France/Gaul or Brittany/Armorica include Gaunnes/Gaul, Avalon (Avallon, or Sein), Broceliande (in Brittany), Carhaix, Camelot (Camaret, Brittany), Arthur's hill (near Gourin in the French Black Mountains), Lac (Beaufort-en-Vallee, Angers), Suesia.
France and Brittany do feature prominently in medieval and modern Arthurian tradition. Some scholars link Arthur and Avalon with Riothamus and Avallon. In the HRB Arthur crossed over to France/Gaul, and Hoel conquered Aquitaine and Gascony, and Arthur held his court in Paris.
However, traditional sources like the HB & the HRB clearly have Arthur as British and/or in "(the island of) Britain", not French/Gaulish/Gallic/Breton and/or in France/Gaul/Brittany.
The Franks were under Claudas or Pharamond not Arthur?
Gaul/Gaunnes/Ganys was the realm of Bors not Arthur.
Brittany/Armorica was the realm of Budic or Ban or Hoel and Walgan not of Arthur.
The Ruteni/Flanders/Terivana was the realm of Holdin not Arthur (HRB).
Bolonia was the realm of Leodegarius not Arthur (HRB).
Neustria/Normandy/Bajocae was the realm of Bedver/Bedivere not Arthur (HRB).
Cenomannia was the realm of Borellus/Bors not Arthur (HRB).
Andegavia/Camus was the realm of Caius/Cheudo/Kay not Arthur (HRB).
Pictavia was the realm of Guitard not Arthur (HRB).
Chartres was under Guerinus Carnotensis not Arthur in the HRB?
Arthur having connections with France/Gaul may point to Kent.
So we can rule out France/Brittany as Arthur's main realm.

Avalon ruled out:
Avalon is of uncertain location. An Irish source has Avalon in the North sea. Some connect Avalon with Hel(i)goland which was called insulam Abalum. Some traditional Arthurian sources have the wounded Arthur taken to Avalon, though others have his resting place in some other place with a different name. But even if this story might be true it shows that Avalon was not Arthur's main realm.
The hall in Afallach might match Afarnach's hall (Pa Gur)?

Orkneys/Orcades ruled out:
The Orkney islands are mentioned in Arthurian sources like the HRB. But the Orkneys were the realm of Gunfasius or Lot not of Arthur. Arthur fought Saxons, and the Saxons were mainly only in the south-east of England/Britain. (Though the HB has Octa and Ebusa sailing up to the Orkneys.)

(Great) Britain/Albion ruled in:
Arthur is clearly connected with the British/Welsh and/or "(the island of) Britain" in traditional sources like the DEB, HB 3, 7, 10, HRB, AC/WA.
However, Arthur can't have romped across almost the whole length and breadth of Britain as some scholars would have it (from Caledonia to Edinburgh to Lindsey to Chester or Caerleon to Bath to Tintagel).

England/Loegria/Heptarchy ruled in:
Arthur is connected with the British/Welsh and/or was in "(the island of) Britain" in early traditional sources like the HB & HRB. Arthur is also associated with Loegria/England in traditional sources (the HRB, etc). There are remnant Arthurian traditions in all of Brittany, Cornwall, Wales, and the North which points to a common origin in England in between these places. The Britons weren't limited to Wales until after Dyrham and "Chester". There was a "salient" of Britons in the London & Essex area, which confirms that the Britons were in England in Arthur's times.
Arthur fought Saxons, and the (Anglo-)Saxons were mainly limited to the south-east side of a line from the Wash to the Solent, or "from the Humber to Dorset". Arthur crossed over to France/Gaul which implies he had to be in England. There was a "salient" of Britons in the south-east in the London & Essex area between London & St Alban's & Colchester (ref Wheeler).

Southumbria ruled in:
In sources like the HRB Arthur is associated with Loegria/England &/or Cambria/Wales rather than Albani/Scotland/North/York.
Arthur fought "Saxons" not "Angles"? And he fought "specifically Kentishmen"? At the estimated time of Arthur the Saxons were mainly limited to the south-east quarter/half of England/Britain southeast of a line drawn from the Wash to the Solent or "from the Humber to Dorset". Badon is agreed to have been in the south.
Arthur's battles were before/until Ida in the HB. Ida was among the earliest of the Northumbrian Anglian settlers. So Arthur is unlikely to have fought Northumbrian Angles.

Isle of Man ruled out:
The only main possible connection of Arthur with the Isle of Man is that some of the Wonders of Britain were in either Mon(a) (Anglesey) or Man (Isle of Man). There is also a Dubglas in Man. But otherwise there is no evidence from traditional sources for Arthur's main realm having been in the Isle of Man.

(North/South) Wales/Cambria/Snowdonia/Caerleon ruled out:
Arthurian places that have been supposed to be located in Wales include Isneldone/Snowdon (Gwynedd), city of the legion (Caerleon or Chester), Cabal's cairn, Gore (Gower), the Round Table (Caerleon amphitheatre or Chester amphitheatre), court at Cardigan, court at St David's, Camelot (Campus Elleti, Glamorgan, or Caerwent/Llanmelin, or Viroconium, Shropshire), Badon (Mynydd Baedan), Camlann (Cwm Llan on Snowdon), Carmarthen, Dinas Emrys (Gwynedd), Arthur's Grave (Berth near Baschurch in Shropshire), Cameliard, Mon(a) (Anglesey), Cruc Mawr.
It is ludicrous to have Vortigern, Ambrosius/Emrys, Merlin, Arthur in Snowdon because they all have traditional time and place links with the Romans, Christians, Kentishmen, and Saxons of south-east in the 5th-6th centuries.
Arthur is said to have fought the Saxons, and there were no Saxons in Wales in Arthur's times, and it is hardly a strategic location, so this rules out Wales as Arthur's main realm. E.g. Evans said "... how Arthur could have fought Saxons in Perthshire and Wales, where no Saxons ever were, is beyond conjecture."
The city of the legion was implied to be in inaccessable Saxon territory in the time of Gildas, which rules out Caerleon.
North Caerleon has been described as being in an "indefensible plain" in Gwent.
The HB doesn't have any "on Usk" added to the city of the legion.
Wales and South Wales were the realms of Cadwallon and Sater so they are not Arthur's main realm.
The Britons were not limited to Cornwall & Wales & the North until after the battles of Dyrham and "Chester". "The Britons ... retire into Cornwall and Wales" (HRB 11:10). "Wurdesten speaks of the Britons leaving their ancestral land when the Saxons occupied it". Gildas says "neither to this day are our cities inhabited ... forsaken & overthrown".
The city of the legion "Cuerlion" is near Isneldone or Snowdon/Sinadon or "Stirling" in Beroul, and some people have said that this doesn't match Caerleon which is not close to Snowdon.
"Snowdon" in Arthurian sources might rather be the Downs of Kent? (There is a Snowdown placename not far from Dover.)
"Carmarthen" might rather be connected with St Martin le Grand at Dover or St Martin's in Canterbury?
Dinas Emrys is named after Ambrosius/Emrys/Merlin who was more likely in the south-east of England.... (Dinas Emrys might be connected with castellum Guinnion or din Eidyn...?)

Scotland/Albani/Dalriada/Caledonia/Highlands/Pictland/Moray /Cumbria/Stainmore/Strathclyde/Kyle /Galloway/Sudreys /Rheged/Ogledd/Manau Gododin/Lothian ruled out:
Arthurian places that have been supposed to be located in Scotland/Albani/Pictland/Galloway include: Eidyn (Edinburgh), Agned (Edinburgh), Alclud/Dumbarton, the Wall, Caledonian wood, Hen Ogledd "North", Londonesia/Lothian, Mureif/Moray, Manau Gododdin, Carduel/"Carlisle", Wedale, Arthur's grave (Eildon hills, Roxburgh), Snowdon (Stirling), Camelot (Camelon, Falkirk, or Camboglanna on Hadrian's wall, or Roxburgh Castle), Avalon (Arran or Iona or Aballava/Burgh), Douglas/Linnuis (Devil's Water at Linnels on Hadrian's wall, or Glen Douglas in Lennox), Bassas (Bass rock in the Firth of Forth), Guinnion (Wedale), city of the legion (Carlisle), Tribruit (Bo'ness, or Dumfries), Badon (Bowden hill, Linlithgow, Lothian), Camlann (Camboglanna in Hadrian's wall, or Camelon in Falkirk), Merlin's Grave (Drumelzier), Ben Arthur, Orkney, Loch Lomond, Dissethach (Skye), Arthuret, Rheged?
Hueil mab Caw was "a Pictish plunderer and chieftain killed by Arthur".
"Arthur was fighting "Saxons" ... and there were none ... in the North in Arthur's time...." (ref Jackson, Loomis, Evans.) (Though some sources like the HB & HRB do claim Hengist and Octa were up North, and though some have Frisians in Dumfries.) "Yet the battles have been located in districts as far apart as the lowlands of Scotland and the south-west of England. There were certainly no Saxons in the latter region until long after this date, while in the north two powerful British states, Rheged and Strathclyde, were holding in check both the beginning of Anglian settlement on the south coast of the Firth of Forth and the small territory of the Niduarian Picts in Wigtownshire and Kirkcudbright."
Arthur's 12 battles were before/until the reign of Ida. Ida was among the earliest Northumbrian invaders/settlers, and moreover the Northumbrian Angles didn't spread very far west and north until ..., so Arthur can't have fought the Northumbrian Angles.
"No source before Geoffrey of Monmouth says that Arthur fought Scots/Picts." (Though Cunedda fought Gwydel/Liethali, and though the Halleluyah victory of Germanus against "Saxons and Picts" has been suggested to be connected with Badon.)
Arthur is traditionally associated with Loegria/England and/or Cambria/Wales rather than Albani/Scotland (refs HRB etc).
Only a few later sources like the Liber Floridus have Arthur as Pictish. The 'Dux Pictorum' of the LF is similar to the Dux Bellorum of the HB.
There are only 5 sites above the Humber, with only 3 sites above Hadrian's wall, and only 1 site above the Antonine wall in a map of Geoffrey of Monmouth's Arthurian Britain, while there are heaps of sites south of the Humber in the same map.
Bass Rock off the north coast of Lothian is not a very strategic place for a battle of Arthur against Saxons.
Lothian was Lot's not Arthur's (HRB).
Rheged was Urien's not Arthur's.
Moray was Urien's not Arthur's (HRB).
Albani/Scotland was Nau's or Augusel's realm not Arthur's (HRB).
Agned (8th of 9) in the HB doesn't match Eidyn/"Edinburgh" (2nd or 6th of 9) in the Pa Gur but matches Ystawinguin (8th of 9).
Eidyn in the Pa Gur may match Guinnion in the HB, and both might match Dover (there is an Edinburgh Hill at Dover)?
The Caledonian wood battle site of Arthur's can't be in Caledonia, but it could be in the Caledonian wood of Caesar's invasion in the Weald area (in Florus etc). The Caledonian wood was near Linnuis, but Caledonia is not near Lindsey/Lincoln.
"Lothian" in Arthurian sources might possibly really be London?
"Albani" in the HRB might be "St Alban's" and/or Guinnion/*Alborum and the Downs (Albion). (Drum Alban in Scotland might be an analogous memory of the Downs?)
Beroul said 'Isneldone/Snowdon' not "Stirling".
Arthur's Seat of Edinburgh is thought to be from Ard-na-Said.
Arthur mac Aedan is not Arthur because Aedan is after the time of Arthur in the ASC etc.
So we can rule out Scotland as Arthur's main realm.

Chester ruled out:
Chester has been supposed to be the city of the legion of Arthur's battles. Chester has also been one of many Camelot candidate sites. The Round Table has also been suggested to be the amphitheatre at Chester.
Arthur fought the Saxons. The Saxons and Angles were not as far north and west in Arthur's times, and this is hardly a strategic location for fighting Saxons. The chronicle of Werburgh has no record of the battle of the city of the legion being fought at Chester. The HRB had the city of the legion at Caerleon not Chester.

Cornwall/West Wales/Devon/Somerset/Dorset/Lyonesse/Southwest ruled out:
Arthurian places that have been supposed to be located in the south-west include Celliwig, Cameliard, Avalon (Glastonbury or Avon), Badon (Bath/Solsbury, or Badbury Rings), Camelot (Cadbury or Chard or Camelford or Tintagel), Tintagel, Lyens/Lyonesse, Camlan (Camel), Summerland (Somerset), Castle Dore, Arthur's Hall (Bodmin Moor), "Totness", St Michael's Mount.
Arthur fought the Saxons. The Saxons were not as far west as Cornwall/Devon in Arthur's times. E.g. Evans said "Yet the battles have been located in districts as far apart as the lowlands of Scotland and the south-west of England. There were certainly no Saxons in the latter region until long after this date...." Bath is unstrategic for fighting Saxons then.
In old conventional sources the Britons/Welsh were not limited to Cornwall and Wales until after the battle of Dyrham 577. The cornered-in location is hardly strategic for Arthur's battling the Saxons. "The Saxons were at its (Dorset's) borders at the beginning of the 6th century, but the British held it until circa 658-710. The ASC records a battle near Somerset or Dorset in 658, which put the Britons to flight."
All of Cornwall, Wales, Scotland, Brittany have remnant Arthurian traditions, which points to a common place of origin in the middle (England).
Glastonbury was not mentioned in the ASC until the 680s.
Tintagel was not associated with Arthur until ....
Somerset wasn't overrun until 658.
The city of Lions/Lyonesse might really be the city of the legion rather than being between Cornwall and Scilly (which latter may be an analogous location).
Cornwall was the realm of Gorlois or Mark or Cador not of Arthur.
Devon was the realm of Geraint not of Arthur.
Summerland/"Somerset" was the realm of Melwas not Arthur.
Dorchester was the realm of Jonathal not Arthur (HRB)?
Bath was the realm of Ur(b)gennius not Arthur (HRB)?
Tintagel was the realm of Aliduc not Arthur in the HRB?
Celliwig may be connected with Celli in the Pa Gur which may match Celidon in the HB. (Celliwig might match Guinnion which was in Celidon wood in an Irish source?)
Castle Dore might be connected with castellum Guinnion and Dover/Dour?
The HRB mentions "Thanet" in its battle of Badon chapter.
So we can rule out Cornwall/Devon/Somerset as Arthur's main realm.

Lincoln/Lindsey/Kesteven/Holland/Co(r)itani ruled out:
Arthurian places that have been supposed to be located in Lincolnshire include Glein (Glen), Dubglas/Linnuis (Lindsey), Kaerluidcoit/Caerlindcoit (Lincoln), Bassas (Bassingham on the Witham), Badon, Thancastre.
Arthur fought 4 battles in Linnuis which is supposed to match Lindsey/Lincoln. Tom a Lincoln also appears in a later Arthurian source.
Arthur fought 12 battles in 9 battle sites. Only 4 battles in 1 battle site where in 'Linnuis', which might imply that Arthur's main realm was not in Linnuis?
Lindsey doesn't feature in the list of Octarchs of the Heptarchy. Lincoln/Lindsey doesn't occur in the ASC until 627/654/678, almost all of the action in the ASC is in the south-east (Kent, Sussex, Wessex) in Arthur's time.
Arthur fought "Saxons" not "Angles"? And he fought "specifically Kentishmen"? We only have Geoffrey of Monmouth's word for Hengist & Octa having been in the North and in "Lincoln/Lindsey" or rather Linnuis.
At the estimated time of Arthur's battles the Saxons were mainly limited to the southeast quarter of England on the southwest side of a line from the Wash to the Solent. The main Saxon Shore forts where only between the Wash and the Solent.
Lincoln/Lindsey was almost an island in Roman times, so may not be very strategic?
If Arthur fought Saxons in Lincoln ("Linnuis") and won, then he suffered quite a reversal to shortly afterwards be fighting Saxons at Chester or Caerleon ("city of the legion").
It is only disputable theory that Linnuis may match Lindsey/Lincoln. The words in regio Linnuis might even be a later gloss? There is no river known to be called Dubglas in Lincolnshire. Linnuis might instead match the likes of coastal Essex or London, and 4 battles being fought there might match this being a strategic location? (Lincoln would seem to not be so strategic a location, though there was a Roman colony there?) The conventional Dubglas candidate in Lincoln is not number 2 of an attested set of 9/12. The conventional match of Linnuis with Lindsey is pretty much only based on the name.
Linnuis is near Celidon in the HB & HRB, but the conventional Caledonia and Lindsey/Lincoln candidate matches are not close.
One of the orthodox Glein candidates (Glen in Northumberland and Glen in Lincoln) "has no distinctive features or strategic fortifications", and one of them "has no mouth" (though does have a confluence).
Thancastre might rather be Ythancester/Othona or Thanet or castellum Guinnion instead of Thong castle in Lincoln?
So we can probably rule out Lincolnshire as Arthur's main realm.

Northumbria/Northumberland/Bernicia/Deira/York/Durham /Ogledd/North/Lothian/Edinburgh ruled out:
Arthurian places that have been supposed to be located in Northumbria include Londonesia/Lothian, Eidyn (Edinburgh), Agned/Bregion (Edinburgh, or Bremenium near Rochester), Glein (Glen), Joyous Garde (Din Guardi, Bamburgh or Alnwick), Manau Gododdin, Ebrauc/York, the city of the legion (York), Hen Ogledd "the (Old) North", Camelot (Cambodunum/Slack), Bassas (Bassington on the Aln, or Bass rock), Badon (Bowden hill, Linlithgow, Lothian).
Arthur's battles were before/until the time of Ida in the HB. Ida was among the earliest of the Northumbrian Anglian invaders. So it is unlikely that Arthur fought Northumbrian Angles. The Anglian slaves that Gregory saw in Rome in 580 couldn't be from Arthur's battles because they were in the reign of Alla who was after Ida. Northumbria doesn't feature in the ASC until 547/560/593/597. Northumbria doesn't feature in the Bretwaldas until between the 5th & 7th some time after Arthur's times. (Bede was Northumbrian and the ASC was partly based on Bede, so no its no use critics claiming "oh but the ASC was only West Saxon records".)
Arthur fought "Saxons" not "Angles"? (Though the LF mentions Englnad/Angleland/Anglia, and the Pillar of Eliseg does mention Angles, and Ivor/Ini attacked Angles in HRB.) And Arthur "specifically fought Kentishmen"? The Saxons were mainly in the southeast between the Wash and the Solent in Arthur's times. "Arthur was fighting "Saxons" (as Nennius clearly shows, and specifically the Kentish men) and there were none near Chester or in the North in Arthur's time...." (ref Jackson, Loomis, Evans.) The main Saxon Shore forts were between the Wash and the Solent. Most of the action in Arthur's time in the ASC was in the south-east quarter (Kent, Sussex, Wessex). Badon is agreed to have been somewhere in the south.
In Roman Britain and the ND the 2 main military areas are the Wall and the Saxon Shore, and Arthur's battles don't match with the Wall sites.
"Cadfan acquires all Britain on this side of the Humber, Ethelfrid the rest" (HRB) surely implies Arthur was south of the Humber?
There are only 5 sites above the Humber in a map of Geoffrey of Monmouth's Arthurian Britain, while there are lots of sites south of the Humber.
One of the orthodox Glein candidates (Glen in Northumberland and Glen in Lincoln) "has no distinctive features or strategic fortifications", and one of them "has no mouth" (though does have a confluence).
Lothian was Lot's not Arthur's. Lot is variously of Lo(n)donesia, Norway or Orkney. Lo(n)donesia/"Lothian" in Arthurian sources like the HB VR and HRB might really be London or Ludanbyrig (Othona/Bradwell)?
York is not known to have been called the city of the legion.
It is only theory that Lancelot's Joyous Garde was Din Guardi or Bamburgh.
The main archibishop of Arthur's time in the HRB is Dubricius of the city of Legions or "Caerleon", not Sanxo of York.
Umberland was the realm of the father of Epinogres not of Arthur.
So we can rule out Northumbria as Arthur's main realm.

Lancaster / Cumbria/Cumberland/Westmorland ruled out:
Arthurian places that have been supposed to be located in Lancashire or Cumbria include Dubglas/Linnuis (Douglas near Wigan), Carduel (Carlisle), Avalon (Aballava/Burgh), city of the legion (Carlisle or Chester), Arthuret, Rheged?
Arthur fought Saxons, and the Saxons were mainly in the east and south in Arthur's times, which makes Lancaster & Cumbria between Chester & Carlisle not overly strategic for fighting them. The Britons were not limited to Wales and the North until after the battle of "Chester" in conventional sources. Arthur's battles were before/until Ida in the HB, and Ida was among the earliest Northumbrian Anglian invaders/settlers. The Northumbrian Angles didn't spread far west until later. So it is unlikely that Arthur fought the Northumbrian Angles to the east of Lancaster & Cumrbia. The (West) Saxons didn't reach as far north and west until Fethanleag and "Chester" which is generally considered to be after Arthur's time.
Arthuriburgum/Etterby probably dates from the later time of Brunanburh?
Urien(s) is variously of Rheged or Moray (HRB) or Bath (HRB) or Gore.
The HRB has the city of the legion at Caerleon not Chester. There is no record of the battle of the city of the legion in the Chronicle of Werburgh.

Everywhere else in the globe/Earth/world/universe ruled out:
We went through all the main areas of the world/universe and going by all the main traditional source texts like the HB Arthur could not be anywhere else other than the places given in this article.

Mercia/Middle Anglia/Midlands/5 boroughs/Shropshire/Hwicce ruled out?
Arthurian places that have been supposed to be located in Mercia or the Midlands include: Legecester/Leicester, Badon (Bardon Hill in Leicester, or Bath/Solsbury, or Buxton in Derby, Bladud father of Leir founder of Leicester), Hwicce, the city of the legion (Chester), Rico/Ridoc/Richiden "Oxford", Cargueit/Warguit/Warwick, Amr's tomb (Wormelow tump, Hereford), Camelot (Viroconium, Shropshire), Arthur's Stone (Hereford), Arthur's Grave (Berth near Baschurch in Shropshire).
Arthur fought Saxons and not "Angles"? And he fought "specifically Kentishmen" (Nennius, Jackson)? The (Anglo-)Saxons were mainly out not in, and south not north, and east not west in Arthur's time. At the estimated time of Arthur the (Anglo-)Saxons were mainly only in the south-east quarter of England/Britain on the southeast of a line drawn from the Wash to the Solent or "the Humber to Dorset". Badon is agreed to have been somewhere in the south.
Most of the action in the ASC in Arthur's time was in the south-east (Kent, Sussex, Wessex). It took 57 yrs for the (West) Saxons to advance 25 miles from their landing place in 495 to Salisbury in 552 (ref Evans), and they only reached "Buckinghamshire/Bedfordshire" in 571. The (West) Saxons didn't extend far north (and west) until Fethanleag 584 and "Chester" 607. The Northumbrian Angles were near the coast at first and didn't extend far west until later.
Mercia doesn't seem to have come to prominence until the times of Penda and Offa, which is sometime after the time of Arthur. Mercia isn't mentioned in the ASC until 644/653/655/676.
The Britons/Welsh weren't limited to Cornwall and Wales and the North until Dyrham and "Chester".
There was a "salient" of Britons in the south-east in the London and Essex area (ref Wheeler) which may imply that the Britons were east of Mercia in Arthur's time?
Arthur is implied to have had access to shore/coast ports (eg "the Porter", "ship/boat Pry(d)wen", "Dover", "Rutupi", "Hamo's port", "France/Gaul", "ships" and "Thanet" in Badon chapter of HRB).
The HRB has the city of the legion at Caerleon not Chester. There is no record of the battle of the city of the legion at Chester in the Chronicle of Werburgh. "Gildas clearly states that this place (city of the legion) is unacessable to British people. If this was Chester it would hardly be unacessable." It is said that there is scanty evidence for the presence of St Julius and Aaron at Chester. "How Deva came to be the name of Chester or the Castra Legionis (whence the Welsh Caer Lleon) is not clear."
Gloucester was under Morvid not Arthur (HRB)?
Worcester was under Mauron not Arthur (HRB)?
Legecester/Leicester was under Jugein not Arthur (HRB)?
Warwick/Warguit/Cargueit was under Arthgal not Arthur (HRB)?
Bath was under Urgennius not Arthur (HRB)?
Ridoc/Oxford was under Boso not Arthur (HRB)?
Boso or Rico/Ridoc/Richiden "Oxford" in Arthurian sources might have really been Reculver (Bassas?) or Rutupi/Richborough?
Legecester/"Leicester" in the list of consuls in the HRB may match the city of the legion in the list of battles sites in the HB.
Badon only appears in a later addition to the Wonders of Britain. Hwicce in the Wonders of Britain might alternatively match Gewissae (Wessex) or Wight or Hicce (Essex)?
"Absence of any mention of Garway in the HB" is possible evidence against the Wormlow Tump orthodox candidate for Amr's Tomb.
So considering all the above we can tentatively probably rule out Mercia/Midlands as Arthur's main realm?

Gloucester/Avon/Bath/Bristol/Severn ruled out:
"Gloucester" is mentioned in Arthur's time in the HRB. Avon has been linked by some with Avalon. Bath has been supposed to be Badon since the time of the HRB. A number of the Wonders of Britain are supposed to be near the Severn.
However, the area is unlikely to have been Arthur's base for his battles.
Arthur fought Saxons. At the estimated time of Arthur's battles the Saxons were mainly in the south-east quarter of England/Britain and were not as far west as the Gloucester area. The Saxons are not supposed to have taken Gloucester, Bath and Cirencester until the battle of Dyrham in 577 in the ASC. So Bath is pretty unstrategic for Arthur battling the Saxons.
Gloucester was under Morvid not Arthur (HRB).
Bath was under Urgennius not Arthur (HRB).
The HRB has Badon/"Bath" near "Thanet".

Saxon Shore / south-east quarter part ruled in, part ruled out:
Arthur fought Saxons (and "specifically Kentishmen"), and at the time of Arthur the Saxons were mainly only in the east and south of England/Britain southeast of a line drawn from the Wash to the Solent (ref Sayles) or "from the Humber to Dorset".
Some say that the south-east is ruled out because the south-east was supposedly all Anglo-Saxon in Arthur's times, however this old view has been questioned in recent decades. There was a "salient" of Britons/Welsh in the south-east in the London & Essex area (ref Wheeler). Sources like History Files and Wikipedia give evidences of Britons still being at sites like Caerwent, Colchester, Walton until quite late. The Fens and the Weald could have been refuge areas. Canterbury and Kent have strong Celtic/British/Welsh connections. Arthur is said to have crossed over to/from France/Gaul (from/to "Hamo's port" and/or "Dover" or "Rutupi") which implies he must have been in the Saxon Shore area.
South-east places mentioned in traditional Arthurian sources include Winchester, Hamo's Port, Appledore, Winchelsea, Dover, Rutupi, Thanet, Chislehurst, Canterbury, London, St Alban's, Clarence?

Surrey ruled out:
There does seem some evidence for that Arthur was in the south-east quarter of England. Arthur fought Saxons and "specifically Kentishmen", and at the estimated time of Arthur the (Anglo-)Saxons were mainly limited to the area on the southeast of a line drawn from the Wash to the Solent (ref Sayles). There was a "salient" of Britons in the London & Essex area.
However, there seems little evidence for Arthur's main realm having been in Surrey itself.

Sussex/Hastings part ruled in, part ruled out:
Sussex sites mentioned in Arthurian traditional sources include Winchelsea, Appledore (Kent/Sussex), Kaicester/Chichester (Wessex/Sussex). "Albani" in Arthurian sources might be the Downs (Albion)?
Arthur fought Saxons and "specifically Kentishmen". At the time of Arthur the (Anglo-)Saxons were mainly limited to the south-east on the southeast side of a line from the Wash to the Solent (ref Sayles). The Jutes ranged from Thanet & Kent to Wight & Hampshire.
"Series of conflicts 455-519" (ASC, Brynjulfson).
"Only landings of Saxons on the coast 488-547" (ASC, Evans).
Arthur's 12 (3 x 4) battles in 9 (3 x 3) battle sites might be connected with the 9 Saxon Shore forts (including Anderida/Pevensey in Sussex), or with the 3 groups of battles in Kent, Sussex and Wessex in the ASC.
There is a suggested connection between the Long Man and Sutton Hoo.
The Weald could have been a refuge for Britons or Saxons.
"Anderida/Pevensey being taken by Aelle is the only record of a [Roman SS] fort being taken by the Anglo-Saxons". (There also might even be some doubt that Andredescester is Anderida?)
"... for neither archaeology nor place-names provide any evidence whatever of early Saxon settlement south of the North Downs." (Evans.)
Sussex "remained a coastal settlement hemmed in by natural boundaries".
"pockets south of the Weald".
"there is no archaeological evidence for occupation by Anglo-Saxons in that area of Sussex between the 5th and 8th century. "
"Sussex disappears from the records after this initial conquest until as late as 685 when its king Æthelwealh died at the hands of the Gewisse."
"... we know nothing of his successors for the next two centuries."
"It is uncertain whether habitation of the fort [Anderida] continued after this event. The fort appears to have been resettled by about the middle of the 6th century by a Saxon community ".
Lewes may possibly be a British/Celtic name (it is disputed among academics/scholars/linguists)?
Local tradition of a battle at Cayburn in 488, and "many skeletal remains of young Saxon men buried on Highdown Hill dating from 2nd half of 5th century" might possibly be connected with a battle of Arthur thereabouts?
However, there is little evidence in the ASC for Arthur's battles during the Sussex battles period between 477 and 492. Aelle is not knowingly mentioned by name in Arthurian sources, though Hengist, Horsa, Octa, and Cerdic/Cedric are. Arthur might have been in the gap between the 1st & 2nd Bretwaldas Aelle 'the Tyrant' & Ceawlin/Cealwin?
Kaicester (Chichester?) was the realm of Cursalen not Arthur (HRB)? (Cursalen or Kaicester might rather be connected with "Jerusalem" and the city of the legion, or Guinnion, and/or Julius Caesar in Kent?)
So Arthur might have been in Sussex but it was probably not his main realm.

East Anglia/Eastland/Norfolk/Iceni/Suffolk/Clarence partly ruled in, partly ruled out:
There is not much evidence for Arthur having mainly been in East Anglia, though there is some possible evidence that he may have partly been there:
Sources like History Files and Wikipedia mention evidence that the Britons/Welsh were still at Caerwent and Colchester and Walton quite late. There was a "salient" of Britons in the London & Essex area. Some sources like Hassell give evidence that the Sutton Hoo ship burial might have been British not Saxon/Scandinavian? "Glass vessels were used by the Britons in the 6th century", and there is a glass vessel at Burgh (Gariannonum, our Glein battle site).
Arthur fought Saxons "from Germany and every province", and he fought "specifically Kentishmen", and at the time of Arthur the Anglo-Saxons were mainly limited to the area south-east of a line from the Wash to the Solent (ref Sayles).
Some sources have thought that Cerdiceshore 495/514 was Great Yarmouth rather than in the Portsmouth/Portsland area (ref GYAM).
Arthur's 9 battle sites might match the Saxon Shore forts, with his 1st and 2nd battle sites Glein and Dubglas/Linnuis possibly matching Garianonum (Burgh, Great Yarmouth) and Othona (Bradwell) or London?
"Procopius, the Byzantine historian, writing soon after the middle of the 6th century, reports that Britons, Angiloi and Phrissones (Friesians) were crossing in great numbers from Britain to the Continent in the first half of the 6th century and that this movement was at its peak during the reign of the Frankish king Theudbert, whose dates are 534 to 548." "Emigration of Angles & Frisians to the Continent 510-555" (Evans.)
"Norfolk has more large Anglo-Saxon cemeteries than the neighbouring East Anglian county of Suffolk".
"The dolichocephali, or long-skulled type of men, who, in part, preceded the English, have been found abundantly in the Suffolk region of the Littus Saxonicum, where the Celt and Saxon [Englishman] are not known to have met as enemies when East Anglia became a kingdom." (Grant Allen, 'Early Britain', chapter 7.)
A modern genetic map posted on Apricity forum showed East Anglia less Saxon.
The Fens might have been a shelter or refuge for Britons (ref Ripley).
The name Aurelius Ursicinus "bear" in the Hoxne hoard might be connected with Arthurian (Aurelius Ambrosius, Arthur arth "bear")?
There is the East Anglian ballad of Arthur of Bradley which might be connected with Arthur & Guinevere?
Clarence in some Arthurian sources has been connected with Suffolk by some.
'Branlant' could be Brancaster/Branodunum?
Caerwent in the Lai d Ywenec could possibly be Norwich?
On the other hand:
Conventional scholars might be right that Sutton Hoo is Saxon/Scandinavian?
East Anglia is not prominent until the 4th Bretwalda Redwald who was after Arthur's time.
The Fens were under the Lord of the Fens, the uncle of Elaine, not Arthur?

Essex/Hicce and London/Middlesex/Trinovantes ruled in:
Essex places mentioned in Arthurian traditional sources include London ("Malory moved Arthur to London"), and St Alban's/Verulam (where Uther died).
Lo(n)donesia/Lothian in Arthurian tradition might be London.
Some have connected Camelot with Camulodunum/Colchester, though this is doubtful.
Arthur fought Saxons. The Saxons were in Wessex, Sussex, Essex and Middlesex. At the time of Arthur the (Anglo-)Saxons were mainly limited to the southeast of a line from the Wash to the Solent. The Saxon Shore extended from Norfolk to Hampshire.
There was a "salient" of Britons in the London and Essex area (ref Wheeler). Sources like History Files and Wikipedia give evidence of Britons/Welsh still at Caerwent and Walton and Colchester quite late. Cadwallon was supposed to be buried at St Martin's church in London according to the HRB.
Arthur's 12 (3 x 4) battles in 9 (3 x 3) battle sites might be connected with the 9 Saxon Shore forts (with 1 in Essex), or with the 3 groups of battles in Kent, Sussex and Wessex in the ASC, or with Vortimer's battles in Kent.
London is the one major place in Britain where there are roads connecting surrounding areas (re Arthur travelling between battle sites).
London or Othona is mentioned in the ASC in 457, and this might possibly match Linnuis in the HB?
(Does the name "Battaills" nearby Othona/Bradwell recall a battle there?)
"Of Middlesex we know little or nothing". "London ... was apparently ignored".
"origins of this kingdom (Essex) are obscure." "did not prove attractive to the early settlers." "... its development late."
"Essex not recorded king until Aescwine 527"?
Essex is not mentioned in the ASC until 604.
Though the main archibishop of Arthur's time in the HRB is Dubricius of the city of Legions or "Caerleon", not the bishop of London.
"Verulam/St Alban's" in Arthurian sources might really be connected with "Jerusalem" and the city of the legion or Guinnion, and the Downs of Kent (Albion).
The White Tower supposedly in London "faced France" which would seem to more likely match Dover or the Anderida area.

Wessex/Gewissae/Hampshire/Meonware (and Wight) ruled in:
Arthurian places that have been supposed to be located in Wessex/Gewissae include: Badon (near Winchester in Tysilio, or Badbury, or Liddington in Wiltshire), Guinnion (Winchester), Camelot (at Winchester in Malory), Round Table (Winchester), Amesbury (Wiltshire), Giant's Dance (Stonehenge).
Wessex places mentioned in Arthurian sources include Wisseans/Gewissae/Hwicce, Silchester, Winchester, Hamo's Port, and Kaicester/Chichester (Wessex/Sussex).
Arthur is said to have fought Cerdic/Cedric in the HRB (Badon chapter & Camlan chapter).
Arthur fought "Saxons" "from Germany" (HB, LF, HRB, Jackson, Evans). The Saxons were in Wessex, Sussex, Essex & Middlesex. At the time of Arthur the (Anglo-)Saxons were mainly limited to the southeast of a line from the Wash to the Solent. The Saxon Shore extends from Norfolk to Hampshire.
"Only landings of Saxons on the coast 488-547" (ASC, Evans).
"There is no evidence from the 6th century to suggest that Saxon settlement had expanded further north than the southern one-quarter of the island." (Ref Brynjulfson.)
"All indicators, though they are few, suggest that Badon was fought against Saxons and the Saxons were in the extreme southern part of the island." (Ref Brynjulfson.)
"Arthur was fighting "Saxons" ... no amount of ingenuity can make Badon, the most probably genuine of them all, anything but a battle against the Saxons or Jutes in southern England." (Jackson, Loomis, Evans.)
"Badonis is probably to be looked for somewhere in central southern England." "Badonis is on historical grounds probably somewhere in the south." "... with the probable exception of mons Badonis none of these places is demonstrably in southern Britain." (Jackson.)
The West Saxons feature in the ASC from 495 as one of the few major parties involved the battles action in the 500s and 600s.
"Series of conflicts 455-519" (ASC, Brynjulfson) sounds similar to Arthur's battles.
"Saxons take 57 yrs to advance 25 miles" 495-552 (Evans).
Arthur's 12 (3 x 4) battles in 9 (3 x 3) battle sites might be connected with the 9 Saxon Shore forts (with 1 in Hamsphire), or with the 3 groups of battles in Kent, Sussex and Wessex in the ASC, or with Vortimer's battles in Kent.
Arthur might come in the gap between the 1st & 2nd Bretwaldas Aelle of Sussex & Ceawlin of Wessex, which is the time of Cerdic and Natanleod? Arthur's battles might have been during the no gains gap 519-552 during in the Wessex period in the ASC.
The West Saxon king was "driven from his kingdom" at Woddesbeorg 591 (ASC).
"The Saxons were at its [Dorset's] borders at the beginning of the 6th century, but the British held it until circa 658-710. The ASC records a battle near Somerset or Dorset in 658, which put the Britons to flight." Dorset is right next door to Hampshire.
One scholar suggested the 2nd battle of Badon may match the battle near Wight and Ashdown and Sussex and Kent in 661 in the ASC?
"scarcity of pagan Saxon cemetaries in North Hampshire and Wiltshire".
"slight if any early West Saxon occupation of Hampshire and Wiltshire (corroborated by scarcity of West Saxon place-names)".
"And in primitive Wessex, while British names survive in central Hampshire and Wiltshire, it is difficult to find early English place-names except in the tiny Jutish area in the south and in the northern parts... were not numerous enough to displace the natives and lived as a ruling warrior class upon tribute...."
"Cerdic and his retainers were one among several groups of adventurers who made their home in South Hampshire and Wilts without being numerous enough to settle down as farmers. They therefore remained as nomadic fighting force, spoiling and levying tribute from the Britons around them."
"conflict of evidence about the way in which the West Saxons arrived there."
"The Romano-British fields at Church Down in Chalton and Catherington, both in Hampshire, Bow Brickhill, Buckinghamshire, and Havering, Essex, were all ploughed into the 7th century".
"the Breton's lands" in Hampshire in the 13th century?
Some Arthurian scholars believe that Gildas wrote at Portchester (our Badon site) or Chichester.
"suspiciously British names of the [West Saxon] leaders" (eg Caradoc/Ceretic & Cerdic, Hwicce & Gewissae).
An archaeological find near our Badon site Portchester was described as "the last resting place of a (perhaps Saxon) local chief"?
Though Salisbury was under Anaraut or Galluc not Arthur in the HRB?
"Winchester"/Guintonhi/Guintruis/Guintguic in Arthurian sources might actually really be Guinnion (Dover?) rather than Winchester though?
Some sources have suggested that Cerdiceshore 495/514 may have been at Great Yarmouth not in the Portsmouth/Portland area (ref GYAM).
Cerdic was interpreter of Hengist in the HB & HRB, which may place Cerdic in Kent/Thanet area.

Kent/Thanet/Weald/North Downs/Kit's Coty ruled in:
Kentish places mentioned in Arthurian traditional sources include Thanet (HRB Badon chapter), Rutupi (HRB Camlan chapter), Dover, Chislehurst (local tradition), Canterbury, Appledore (Kent/Sussex), Kit's Coty.
Kit's Coty house is traditionally considered to be the site of battle where Catigern died.
Vortigern and Merlin have a traditional claimed connection with Chislehurst caves (refs Walker).
Gawain is supposed to have died at Rutupi or "Dover".
Riculf/Raculf in the HRB might be connected with Reculver/Regulbium? ("Racuulfe... which stands at the northern mouth of the river Genlade" in Bede.)
Arthur is said to have crossed over to/from France/Gaul from/to Hamo's Port or Dover or Rutupi.
There was a "salient" of Britons/Welsh in the London & Essex area, which is next door to Kent (ref Wheeler).
Canterbury and Kent have Celtic/British/Welsh names and associations.
St Martin's church in Canterbury was a British church.
An orthodox scholarly source said that there were "few/little or no Saxon cemetaries in Canterbury".
The Medway is supposed to have been the border between the Kentishmen and the men of Kent.
"It is by no means impossible that some of the Kentish distinctions are based in part on Romano-British influence.... It is difficult in any other manner to account for the fact that Kent alone preserved a resemblance to its Roman past.... ... may hold a memory of pre-Saxon agricultural arrangements ... due to the presence of peasants of Romano-British descent...."
"Glass vessels were used by the Britons in the 6th century". There is a glass vessel at Dover (Guinnion?)
Mari Lwyd in Caerleon is similar to Hoodening in Padstow (Petroc's, Cornwall), & in Kent, & in Cheshire.
Cadwaladr invaded Wight and Sussex and Kent in [661? &] 686 (refs ASC)?
Arthur fought Saxons "from Germany and every province", and at the time of Arthur the (Anglo-)Saxons were mainly limited to the southeast of a line from the Wash to the Solent. The Saxon Shore included Kent. Cerdic was interpreter of Hengist in the HB & HRB, which may place Cerdic of Wessex in Kent/Thanet area.
"[Those who control the South-East have the main power/hold in Britain.]"
Some scholars agree that Nennius seems to imply Arthur fought "specifically Kentishmen" (because Arthur's battles came between Octa and Ida, refs Collingwood, Evans). "In one Welsh text Arthur is represented as on his way with his whole army to fight an Osla Gyllellvawr (Osla or Ossa of the Big Knife) at Baddon. .... In the Dingestow version of Geoff of Monmouth's HRB it is stated that Ossa was a cousin of 'Otca mab Heingyst', i.e. Octa, son of Hengist. Here we seem to have a tradition that Arthur did fight Octa-Oisc, son of Hengist."
Arthur's 12 (3 x 4) battles in 9 (3 x 3) battle sites might be connected with the 9 Saxon Shore forts (with 5 battle sites in Kent), or with the 3 groups of battles in Kent, Sussex and Wessex in the ASC, or with Vortimer's battles in Kent.
The Jutes/Kentishmen figure as one of the few major people/places involved in the battles action of the 400s and 500s. Kent features in the ASC from 449-473/488 and 552/560-616, while places like Lincoln do not appear until somewhat later. Kent features in the list of Bretwaldas at around about Arthur's time. (0th Bretwalda Hengist, 3rd Bretwaldas Ethelbert.)
The Caledonian wood of Caesar's invasion was in the Weald area.
The Weald could have been a refuge (ref AC Doyle?)
Jutish phase 450-500 (Evans).
"Series of conflicts 455-519" (ASC, Brynjulfson) sounds similar to Arthur's battles.
"c460 Saxon victories in the ASC largely confined to coastal areas."
"Period of minimal Saxon activity 466-73."
"On affairs in Kent the ASC is entirely silent from 488 until 565" (Evans).
Frankish influence 510-570 (Evans).
Not sure if the date of this matches or not but at Burham near our Caledon battle site "a cemetery was found with six skeletons all of whom showed injuries caused by weapons. Three had single long sword cuts to the left side of the skull. The other three had multiple injuries - one had been hit three times on the left side of the skull, another had been hit in the spine by a projectile, either an arrow or a javelin, which probably disabled him and a single sword cut to the head."
Evidence of the Kentish SS forts being in use then includes: "Medieval and later pits were also found [at Reculver]."
"The church [at Richborough/Rutupi] was probably built at the end of the 4th century or at the beginning of the 5th century. It seems plausible that the church was built of wood." "there is evidence of a large Roman population here [Richborough] in the early 5th century, some of them worshipping in the Early Christian church discovered in a corner of the fort."
Hawkes etc say that Richborough is one of the best preserved Roman sites in Britain.
"Numerous Saxon cemetaries found at Sarre, Ash, Kingston" might be connected with battles there?
This period in the history of Kent described as "most perplexing problem of the period".
"the crux of the problem of the Jutes in Kent could be resolved if only we could date precisely the archaeological discoveries" ... "we do not know how long the intervals were between the making of one object and the making of another."
"Even in Kent, an area of rich early Anglo-Saxon archaeology, the number of excavated settlements is fewer than expected. However in contrast the counties of Northamptonshire, Oxfordshire, Suffolk and Cambridgeshire are relatively rich in early settlements."
"The name "Eccles" comes from the Latin word "ecclesia" meaning church, suggestions that a post-Roman Christian community existed in the village beyond the Roman withdrawal and into the Saxon period ...."
Arthurian has French/Frankish/Gaulish (& Breton) ties, which means we are looking for an area which is neighbouring/bordering France, and Kent is the best match for this.
Mintz's paper suggested possible connections between Arthur/Merlin and Ares/Mars and St Martin. There are a few churches of St Martin in Kent in/at or near or connected with our battle sites (including St Martin le Grand in Dover, St Martin's in Canterbury).
Kent might be hinted at in some Arthurian names like Kentigern, Gwent. Some think that Kent and Canterbury are from cant "crooked/bent" which some think Camlan is also from. Cadbury in Somerset might be a memory of Canterbury or Cayburn?
Dyfrig/Dubricius (arch)bishop of the city of legions in the HRB & AC might be connected with either Mandubracius or Dubris/Dover or Durovernum/Canterbury or Durobrivae/Rochester. Dubricius as "chief (arch)bishop of Britain" links with the archbishop of Canterbury. Dubricius is near "Thanet" in the Badon chapter of the HRB.
The castle/tower in the Modena Archivolt picture looks somewhat similar to Dover lighthouse (our Guinnion battlesite).
Our major candidates for Arthur include Vortimer or Ethelbert who were in Kent. (The names Ut(h)er and Arthur are similar to Urtigernus/Guorthigirn/Gwrtheyrn/Vortiger/Vortigern/Vortigen and Gwrthefyr/Vortimer?)
The city of the legion or "Caerleon" was "2nd Rome. … chief city of the isle of Britain … priveleges & rank … principal Archbishop…." "one of the most important cities in Britain". It was "Arthur's capital" and he "loved & honored Caerleon on the Usk more than any other place". This may match Rutupi/Richborough which was "their primary station", "became the metropolis", "was of such celebrity that...", "was the station of the 2nd Augustan legion, under the count of the Saxon coast, a person of high distinction", "the primary station of the Romans in Britainnia...", "Watling Street proceeded from Richborough". "there is evidence of a large Roman population here [Richborough] in the early 5th century...."
St Julius of the city of the Legion seemingly may originate from Julius Caesar who landed at Dover/Deal/Walmer/Richborough/Ebbsfleet where our city of the legion Richborough/Rutupi is located. Gai Campi also might originate from Caius Julius Caesar?
According to Hassell, Malory said there was a "great white palace of white marble" at Camelot, and coincidentally the building on top of the large (white) cruciform platform at Richborough was "faced with Italian marbles".
The Jutes versus the Saxons with the Angles laid waste between them in the ASC, and the war between Ethelbert of Kent and the West Saxons in the ASC might possibly be connected with Arthur versus the Saxons? Often in history earlier waves of invaders become allied with the natives, and we have seen that Kent has British ties.
Other scholars who have placed Arthur in or near the same area include Nennius (Octa), Geoffrey of Monmouth ("Thanet"), Malory (London), Wheeler (Essex, London), Collingwood (Kent, Sussex) and Evans (Kent, Thames).
Charles P. suggests that "Arthur's war in England was fought in Kent and the East Midlands, perhaps as far north as Lincolnshire, but not in the West Country."
"It is at Cardiff, therefore, on the one hand, and at Richborough on the other, that we must look for the history of Caerleon in the fourth century, and it is possibly in the amphitheatre which lies buried outside the walls of Richborough that the lost century of 'King Arthur's Round Table' may yet be found."
Though Dorobernia was under Kinmare not Arthur in the HRB?

Refs include:
24 kings & 33 cities document
ASC
Sheila Brynjulfson
Collingwood
Deniker
Evans Arthurian Campaign
Geoffrey of Monmouth HRB
Gildas DEB
GYAM
Jaqueta Hawkes
Alan Hassell on Sutton Hoo
History Files
Kenneth Jackson Once Again Arthur's Battles
Local traditions of Kent and Sussex
Malory Morte de Arthur
Nennius/Mark Historia Britonum & Wonders of Britain
Notita Dignitatum
Charles P.
Procopius
Ripley
Sayles.
Tysilio
Mortimer Wheeler
Wurdesten
Wikipedia.