When was King Arthur?

This is a half finished post on When was King Arthur according to early traditional source texts? We are just posting it for storage and for reference use for ourselves and others.
Since we recently finished articles on Where was King Arthur? and Who was King Arthur? we should complete the effort by also posting on When was King Arthur?
(Note: All of the dates entries are from early sources, and all the dates are for the person/place/event mentioned in the first lines except for just a few which are "crazy" faint possibilities like the ones for Nennius & Ninnian and Gildas & Hilda.)


When was Arthur?

Arthur comes after Bardus in Holinshed & Hoeh. Bardus has date 1922-1819 (Hoeh).

Arthur comes after Brutus in the HRB. Brutus has dates: time of Eli (HRB), 1149-1125 (Hoeh), 1108 (24 kings), Brutus the 1st consul of Rome? ... (Spain)? Brutus murderer of Caesar? Robert Bruce?

Arthur comes after Membyr/Mempricus 1009 (24 kings) in the HRB

Arthur comes after Evrog/Ebrauc 969 (24 kings) in the HRB

Arthur comes after Brutus 2 Darian Las 929 bc (24 kings) in the HRB

Arthur comes after Lleon/Leil 917 (24 kings) in the HRB

Arthur comes after Rhun/Hudibras 892 (24 kings) in the HRB

Arthur comes after Bladud in the HRB. Bladud has date 929-909 (Hoeh), 853 (24 kings).

Arthur comes after Leir/Lear/Llur 834 bc (24 kings) in the HRB

Arthur comes after Dunwal Mulmutius 441 bc (24 kings) in the HRB.

Arthur comes after Beli 401 bc (24 kings) in the HRB

Arthur comes after Gwrgant/Gurgiunt 375 (24 kings) in the HRB

Arthur comes after Cyhylyn/Guithelin 356 (24 kings) in the HRB

Arthur comes after Heli/Beli mawr 58 bc (24 kings) in the HRB

Arthur comes after Caswallawn 47 (24 kings) in the HRB

Arthur comes after Caesar 60 (ASC), 47 bc (HB) in the HRB

Arthur comes after Cymbeline 4 bc (24 kings) in the HRB

Arthur comes after Guiderius 17 ad (24 kings) in the HRB

Arthur comes after Claudius 47/46 ad (HB, ASC) in the HB & HRB.

Arthur came after Christ in the HRB & 24 kings. Christ has dates during Maccabees (Yeishu ha Notsri, Talmud), 4 bc (24 kings), 1 ad (ASC), 3 ad (ASC), ad 17 (24 kings), 30 ad (ASC), 33 ad (ASC).
"The Lord Jesus Christ" in Roman Catholic and Arthurian might really be Zeus or Jupiter Capitol... or Julius Caesar or Augustus or Claudius.

Arthur comes after Joseph of Arimathea 12-30 or 63/76 ad.

Arthur came after king Lucius & pope Eleutherius 79 (OEC), 156 (HRB), 161 (OEC), 167 (HB, ASC), 181 (24 kings), 189 (ASC).
"Pope Evaristus" is really emperor Nerva.
"Pope Eleutherius" is probably emperor Lucius Verus.
Eleutherius might match Ebur in the AC.
King Lucius might match Lucius Artorius Castus?

Arthur comes after Coel/Cole in the HRB & 24 kings. Cole has date 265 (24 kings), king C... of Wessex.

Arthur came after the martyrdom of Sts Alban & Julius & Aaron & Amphibalus in the persecution of Diocletian 209? 283/287 (ASC)? 298-303/304-313, St Alban features in the story of St Germanus 429, St Alban's features in story of Uther (HRB).
St Julius might really be from Julius Caesar.

Arthur comes after Maximus in the HB & HRB & 24 kings. Maximus has dates 381 (ASC), 383 (24 kings).

Arthur comes after Gratian 379 (ASC), 381 (ASC)

Arthur comes after Honorius refuses call for help in 410.
(Telemachus was martyred during Honorius' reign.)

Arthur came after the Romans left Britain 348 yrs (HB), 409 yrs (HB), 409 (some Romans go to Gaul, Ethelwerd), 418 (some Romans left to Gaul), 447 yrs (HB)? 465 (R of C), 470 yrs (ASC), 485 (Ethelwerd).
Though there has been a theory that Arthur might match Lucius Artorius Castus, or Count Theodosius the brown bear. Some think Arthur might have had Roman blood.

Arthur came after the Groans 443 (ASC), 446.

Arthur came after Agitius/Ayitius/Aetius who has dates: 423 (Avitus)? 432/437 (Aetius), 443 (Atilla the Hun ASC)? Severus Aequantius? Gratian Aequantius 447? 446-454 (groans, Aetius) Avitus 455-456? Egidius (Gregory of Tours)? Anthemius? 517 (Agapitus)? 535-536 (Agapetus)?

Arthur came after Vortigern in the HB & Hergest & HRB.
Vortigern's dates are 400 (HB), 426 (Hergest), 447 (HB), 449 (ASC, Ethelwerd), 455 (ASC).
Though Vortigern is mentioned by some as a candidate for Arthur, and/or Arthur might have been Vortimer who was during Vortigern's reign?

Arthur came after raids by Scots/Irish/Gwydel and Picts which lead to the Britons appealing to the Romans to aid them, and when the Romans ignored appeals they called in the Saxons to aid them. The raids of the Scots and Picts have been variously dated: late 380s (Maximus), 397 (Picts/Irish/Saxons), 408/410 (attacks by Scots/Picts/Saxons), when St Patrick was a boy, before Cunedda and Cadwallon battled them.

Arthur came after the invasion of the Saxons.
The dates for the invasion of the Saxons are 350, 360 (Germanics, Wiki), 367/368 (Germanics, Theodosius), 380 (SS forts), 397 (Picts/Irish/Saxons), 4400 (Stilicho vs Saxons, Richard of Cirencester), 400 (HB), 406 (Germans in Gaul sever contact between Britain & Rome), 408/410 (attacks by Scots/Picts/Saxons), 421, bef 429 (Germanus), 438 (ACb), 441 (Gallic Chronciles), 443 (ASC), 446, 447 (HB, AC), 449 (Hengist, ASC, Ethelwerd), 449-456 (Bede), 469 (ACb), 473 (Brynjulfson), 477 (Aelle, ASC, Ethelwerd), 494/495 (Cerdic, ASC), ca 500 (Northumbrian Angles, Wiki), 501 (Port, ASC, Ethelwerd), 514 (Stuff, ASC, Ethelwerd), before 547 (Ida, ASC), ca 550 (Essex, Wiki).

Arthur came after the revolt 452 (Wiki) and/or the Long Knives massacre of 460 in the HRB.

Arthur came after Hengist 449 (ASC), 452, 488 (ASC, Ethelwerd).

Arthur came after Horsa 455 (ASC, Ethelwerd) in the HB & HRB

Arthur comes after Vortimer 455/456 (ASC) in the HB & HRB. Though Vortimer is a candidate of ours for matching Arthur.

Arthur is not mentioned by that name in the Gallic Chronicles of 452 & 511.

Arthur comes after St Germanus of Auxerre in the HB & HRB. Some think that Badon in Bede may be the Halleluyah Victory of Germanus. Arthur was dux bellorum, Germanus was dux proelli or dux belli.
Germanus has dates: came with Patrick (HB), 429 (Halleluyah Victory), 447 (2nd visit), 480/480s (Vita/Life of Germanus).

-----

Arthur comes after Leo & Easter date in the AC. The date of Badon is considered by some to maybe be connected with the 84 yrs Easter cycle (easter cycle start/end date 438 to Badon 482). The 2nd battle of Badon coincides with an Easter date.
Easter dates from sources include: 438 (McCarthy & OCroinin), 453 (Leo, AC), Dionysius Exiguus 532 (EH, Florence), 626 (ASC), 634 (ACb), 640 (ASC), 655 (ASC), 661 (Pontesbury, ASC), 665 (Badon, AC), 685 (ASC), 703 (Adamnan EH), 710 (EH), 716 (ASC, EH), 755 (Elvod, OEC), 768 (AC), 774 (ASC).

The 128 yrs from Vortigern to Badon in Hergest has been dated: 390-518 (Kamlesh G), 425/426/428-554 (Hergest, CB, Jones), 449-577.

Arthur's father Uther Pendragon is associated with a sidus or comet star. Dates for comets include 441/442 / 5th cent (Northampton, Idatius/Marcellinus), 451/453 (Halley's, Atilla), 498/499 (Chronicle of Edessa / Roger of Wendover), 1500 ya / 500 ad (Encke's, Forsyth Petroglyph)? 530/535 (Halley's, Michael the Syrian / John of Ephesus)? 538 (Camlan, Roger of Wendover), "Pendragon comet 574" (Hassell), 650 (AC), 676 (AC), 677 (Ethelwerd), 678 (ASC), 684 (Broomstar, Halley's, 1 source of Nuremberg chronicles, Chinese), 729 (ASC), 891 (ASC), 905 (ASC), 975 (ASC), 995 (ASC), 1066 (ASC), 1097 (ASC).
Though scholars say that Arthur's surname Mabuter in the HB may be a title meaning horrible son rather than meaning son of Uther, which means Uther and Arthur might be the same person? *

Arthur comes after Ambrosius/Aurelius in the HB & HRB. Arthur lead at Badon in the HB may match Ambrosius seems to have lead at Badon in the DEB. Ambrosius has dates 429-450/456 (1st victory, Bede)?

Arthur's battles are just after mention of Octa in the HB.
Arthur fought Osla/Ossa at Badon in Rhonabwy, which might match with Octa/Ossa in the HRB.
Octa/Aesc has dates 455 (ASC), 456, 457 (ASC), 465 (ASC), 466, 473 (ASC), 488 (ASC).

Pharamond is one of the knights of the Round Table in some later stories.

Arthur is implied to have fought Saxons and "specifically Kentishmen" in the HB (HB, Jackson, Evans). The Jutes and Kent have dates 449-473 (ASC), 488 (ASC), 552 (ASC), 560-568 (ASC), 596 (ASC), 601 (ASC), 604 (ASC), 616-617 (ASC), 633 (ASC), 640 (ASC), 664 (ASC), 673 (ASC), 676 (ASC), after 685 (ASC), 686-687 (ASC).

Arthur's dates range in early traditional sources (and in modern scholars) is: Draco & Ursa (Hitching), 3349 bc (Waddell), Bronze Age (Drou or Dale), Ursus 776-742 bc (me), the bear in Daniel, Deoartavo(i)s 47-67 (me), 180 (LAC, Infopedia) 350/383 (Morris)? 421 (Arthur &/or Gildas, CMSM &/or another source)? 450/454 (Grail, Malory), not 452 (no Arthur, Gallic chronicles), 470 (Badon, HRB), not 511 (no Arthur, Gallic chronicles), 516/518 (Badon, AC, 24 kings), 519 (Arthur subdues Ireland), 537/539 (Camlan, AC/WA), 540 (Shakespeare & the Welsh)? 542 (Camlan, HRB), 546 (Badon, one AC version), 554 (Badon, Hergest), "abdicated in 574 (541 yrs after the crucifiction)", 576 (Camlan, Hergest), 631-650 (Arthus, Swedish king list), 640 (Shakespeare & the Welsh)? 650 (Arthur, Wace, Morris), 700 (Infopedia), 807 (Arthgen, AC, Evans, me), Alan of Brittany (Zoetropo).

Arthur is contemporary of pope Supplicius in the HRB. The Arthur candidate of some Riothamus was contemporary of pope Simplicius.Supplicius is surely Simplicius 468-483, he is not likely to be the only other possible candidate Symmachus 446 or 485 or 498-514 or 522.

Arthur might have been in the gap between the 1st & 2nd Bretwaldas 491-556/560, and a 2nd Arthur might have been in the gap between the 7th & 8th Bretwaldas 670-802?

Arthur's battles might have been in the no gains gap 519-552 of the ASC.

Arthur fought Cerdic in the HRB. Caradoc is (a knight of the Round Table in) some King Arthur stories.
Cerdic's dates range is: interpreter of Hengist (HRB), 494/495-516/534 (ASC). (See also Ceretic of Elmet below.)

Arthur was contemporary of Geraint/Grant/Gerentius/Wuthgirete of Devon in some stories. Geraint's dates are either 501 (ASC) or 710 (Ethelwerd, ASC).

Arthur was contemporary of Gildas (Sts Lives, DEB), and Badon was 44 yrs after Gildas' bday or on Gildas' bday, and was 10 or 44 yrs before Gildas wrote.
Gildas' dates range in early traditional sources is 421 (CMSM or other source)? "gap in Gildas 500-550" (Carroll)? 512 (died, W of M), 546 (wrote, 1648 translation), 565 (to Eire, AC), 570/572 (died, AC), 680 (Hilda, ASC, Ethelwerd)?
Though Arthur is not mentioned in the DEB.

Gildas was contemporary of Ainmericus/Ainmire who has dates 548-551 or 566-569 or 573-576.

Arthurs 9th battle was at Urbslegionis or "Caerleon" the city of the legion. Legions in or near Roman and Sub-Roman Britain:
"Caer lleon on dee 917 bc",
"Caer lleon on usk 401 bc"
Caesar landed at/near Richborough 60/47 bc,
legions in Claudius invasion at Richborough?
Colchester (43-49/55),
Mancetter (43-58),
Richborough & Fishbourne (44-5),
Burrium (55-66),
Watling Str (60),
Menai (60-1),
Colchester (60-1),
Wroxeter (68-80),
Legio 9 Hispania at York 71-121,
Second legion from Gloucester to Caerleon 74/75 ad (till c 255)
Gloucester (75),
Chester & Caerleon 78
Eboracum/York & Virconium/Wroxeter & Deva/Chester & Isca/Caerleon 80,
Inchtuthill (83-7),
Mons Graupius (84),
Hadrian's Wall (120),
Bo'ness/Bridgeness (142),
Severus 2 legions York,
Eboracum/York & Deva/Chester & Isca/Caerleon 180,
Legio Valeria Vict at Chester 88-250
Rutupi/Richborough (Saxon Shore forts ca 270/293, Richborough built 277-285 or 305 or ca 395, legio Augusta garrison at/to Rutupi/Richborough (from Caerleon) 305, legion 2 Augusta at Rutupi in ND 395/400s/420/420s/428 until 15th C/1542/16th C/before 1672, church built end 4th or beg 5th cent, large popn ear 5th cent),
Maximus withdraws his legions from Britain 383,
Gratian with 2 legions sent away, Romans granted 1 legion,
Stilicho removed legion/force 401,
legio 6 Victrix, one of the two legions recalled 402
Constantine 3 withdraws remaining legion Augusta to Gaul 407,
"a late relief force sent ca 420 or so to help the Britons",
Logiore & soldiers of Coroticus in Life of Patrick?
forces from Caerleon transferred to Cardiff by early 5th cent,
Legio 2 Britannica from Gaul early 5th cent,
Legio 2 Britannica just 1,000 strong by ear 5th cent,
Leo (AC)?
Natanleod & 5000 (508, ASC)?
Pol Aurelian de Leon (David under 514, synod ca 545, died 575)?
"Caerleon on Usk ad 516"
"British legion near Orleans 530"?
St Dalmas / "legion of Britons at Loire in 536"?
Liganburh 571 (ASC)?
synod Urb(i)s Legion(is)/Legionum 601 (AC),
Legercyestre 606/607 (ASC)
battle Caer Legion 613 (AC),
siege Exeter ca 630?
Sentleger / St Ledger 635?
Caerleon (800),
Legaceaster (894, ASC)
"Civitas Karlegion / Legeceastre" (Florence of Worcester, 894 & 908),
"city of legions" (973, ASC?)
"the legionaries of Britannia Minor" (Roman Martyrology 2004),
St Loyes / Exeter (2010).

Arthur lead at the battle/siege of Badon in the HB, AC, HRB.
Badon's dates range in early traditional sources (and/or modern scholars) is 429 (Bede)? 430-440 (Higham), 450/454 (Malory), 470 (HRB), 482 (from easter cycle), 485 (Snyder), 485-520 (Wood), 487 ad (454 yrs Malory), 490s (Wood), 492/493 (DEB, Bede), 494-497 (Morris), 500 (Dumville), 501 (DEB, Evans), 516 (AC), 546 (one AC version), 554 (Hergest), 577 (Badon/Bath, ASC), 634 (ACb), 661 (Badon 2, Pontesbury, Hunt), 665 (Badon 2, AC), 675 (Badon 2, Bedwin, Charles, ASC), 939 (Badon/Brunandune)? 940 (HB)?
10 (Badon-Gildas, DEB), 12th (Glein-Badon, HB), 22 (Badon-Camlan, AC), 44 (Saxons-Badon or Badon-Gildas, DEB), section 50/56 (Arthur's battles, HB)? 63 (ACa)? 71/72 (Saxons-Badon, ACb), 128 (Vortigern-Badon, Hergest), 150 (Saxons-Badon, DEB), 222 (Saxons-Badon 2, AC/WA).

Arthur's great victory over the Saxons on St David's birthday/day was in 540 or 640 (Shakespeare & the Welsh).

Arthur's spear was named Ron in 470 (HRB). Rhun was son of Urien 626 (AC). Rhun was son of Maelgwn.

Arthur's battles were until Ida in the HB.
Ida's dates are 547-560 (ASC, Ethelwerd) or 584.

Arthur's battle of Camlan has dates range of 537 (AC), 542 (HRB, Stow & Warner), 576 (Hergest), after Arthuret (Triads).
10 (Camlan-Maelgwn), 22 (Badon-Camlan, AC), Triad 84, 92/93 (Saxons-Camlan, AC), cw126 (Camlan).

Arthur's battle of Camlan, and Maelgwn's death are associated with plagues, and "the plague is not mentioned in Gildas"?
Plagues dates include: 537/539 (Camlan, AC), 544 (pestilence, Columba)? 547 (Maelgwn, Justinian, AC), 590-604 (Gregory, Book of Hours), 639 (Emaus), 644 (London), 664 (ASC), 682 (AC), 683 (AC). *

Arthur was after Merlin in the HRB, and contemporary with Merlin in some stories, or before Merlin 573 in the AC.

Arthur is contemporary with Peredur in some stories, or before Peredur 573 (AC), 583 (AC), 593 (Hergest).

Arthur is contemporary of Dubricius in the HRB, or before Dubricius 612 (AC).

Arthur was contemporary with Urien in some stories, or before Urien in the HB. Urien's dates range is 567, or 575 (Wiki), 590, after 596 (Wiki), 600.

Arthur's grave is supposedly at Glastonbury, but Glastonbury has a founding date of 688 in the ASC.

-----

Arthur came before Arthuret in the AC/WA, or during according to Ardrey which might be supported by the Triads having Arthuret between Goddeu (which is compared with Celidon) and Camlan.
Arthuret has dates range: before Camlan (Triads), 573 (AC), 593 (Hergest).
10? Triad 84, 128/129? 152?
Arthuret 2nd/middle of 3 between Goddeu (Caledon?) & Camlan might match either Arthur of Guinnion, or Arderit/Tribruit, or Anderida, or Andredes weald (Caledon).
Gwendoleu at Arthuret resembles Guinnion & Dover.
Arthuret was near the Caledonian wood, and Guinnion was in the Caledonian wood in an Irish source.

Arthur comes before Y Gododdin 538 or 570 or 596 (Wiki), 598 (Wiki), 600 (Wiki), or 638 (Wiki). (Though Arthur might match a person in the Y Gododdin?)

Arthur is considered to have come before Bedford 571 (ASC) &/or Dyrham 577 (ASC)? Though some have connected Badon with Bath in the 577 ASC entry. 3 of the sites in the 571 ASC entry have similar names to 3 of Arthur's battle sites in the HB (Bensington/Bassas, Egonesham/Ignesham/Guinnion, Liganbugh/Urbslegionis).

Arthur is implied to have come before the separation of the Cornish & Welsh at Dyrham 577, and the separation of the Welsh & North at "Chester" 601 (AC), 602 (Hergest), 607 (ASC), 613 (AC), 616.

Arthur comes before Constantine in the AC & HRB. Constantine has dates 407, 589 (AC). (Except for modern theories that Arthur might match Cuneglas who was contemporary with or after Constantine.)

Arthur/Badon came before Maelgwn in the 24 kings & AC & HRB & HB & DEB.
Maelgwn's dates are 547 (AC), Mailcun 559? Coinmagil 577 (ASC)? 581 (24 kings), 586 (Hergest), at Arthuret (DMT).
10 (Camlan-Maelgwn), 146 (Cunedda-Maelgwn).

Arthur comes before Ethelbert in the HRB. Ethelbert has dates 560 (ASC), 568 (ASC, Ethelwerd), 594 (AC), 616 (ASC).

Arthur is before Aedan 558 (AC), 603 (ASC), 607 (AC), 651 (ASC). Though some scholars identify King Arthur with Artuir mac Aedan who fought battles during Aedan's reign.

Arthur comes before "Chester" 601 (AC), 602 (Hergest), 607 (ASC), 613 (AC), 616.
Though some scholars identify the battle of "Chester" with Arthur's battle of the city of the legion

Arthur comes before Ceretic of Elmet 604-614, 616 (AC), 619. (See also Cerdic & Caradoc above.)

Arthur comes before the battle of Cirencester 577 (ASC), 628 (ASC), 629 (Ethelwerd).

Arthur comes before Penda in the HRB. Penda has dates 626 (ASC), 628 (ASC), 629 (Ethelwerd), 633, 645 (ASC), 655 (ASC, Ethelwerd), 657 (AC).

If Arthur was a Celtic christian then he came before the synod of Whitby 664.

Arthur comes before the 2nd battle of Badon 634 (Badon 2, ACb), 661 (Badon/Potesbury, Hunt), 665 (Badon 2, AC/WA), 675 (Badon/Bedwin, Charles).

Arthur comes before Cadwallon 629 (AC), 630 (AC), 631 (AC), 633, 634, 635 (24 kings)

Arthur comes before Cadwaladr 658, 664 (Hergest), 682 (AC), 684 (Ethelwerd), 685 (24 kings, ASC), 686 (ASC), 687 (ASC), 688 (ASC), 689 (HRB).

Arthur comes before pope Sergius 688 (ASC), 689 (HRB).

Arthur lead at Badon. Badon came before Bede's EH 735 (AC). Though Arthur is not mentioned by that name in the EH.

Arthur came before the HB of Nennius/Mark 55 bc (HRB), Nemuivus found at Bodleian 5th-8th cents? 542/547 (HB)? ca 555-595 (Nynnio ap Erb)? long before 560 (Ninnian, ASC)? 613 (Nennius & Elvod), "evidence vatican ms HB old as 674", that he had/used earlier sources dating ca 679/680, late 7th cent (Brewer's/Cooper), 796 (OEC), "claims of Mark/Marcus the Anachoret 822 to authorship of HB", 858 (421 + 428/438, Mermenus, HB), 946 (HB), 976 (HB), 984 (HB date of some), 989 (447 + 542, HB), 994 (447 + 547, HB, OEC), 10th cent (Mark's date, Gunn), 1071 (Irish HB)? Dumville on Nennius not before 12th century,  "12th cent historians refer to HB under name of Gildas / ascribed it to Gildas".
The HB of Nennius/Mark mentions Elvod who has dates 613 (Nennius & Elvod), 755 (HB apology/prologue footnote in OEC), 768 (AC).
The HB mentions Merfyn & Edmund. Merfyn has date 844 (AC) or 858 (HB) or 904 (AC). Edmund has date 946 (HB), 947 (AC), 976 (HB), 989 (HB).

Arthur comes before Charlemagne 800.

Arthur came before the Norman conquest 1066.

Arthur came before the HRB of Geoffrey of Monmouth 1136/1152. (Except for modern theories that Arthur is Alan of Brittany and Lancelot is modeled on ..., and that the Knights of the Round Table match king ...'s round table.)

Arthur came before the Morte de Arthur of Malory 1471.

Arthur came "once" before the "future".

Abbreviations:
24 kings = 24 kings & 33 cities document
AC = Welsh Annals
ASC = Anglo-Saxon Chronicle
CMSM = Chronicle of Mt St Michel
DEB = Gildas
EH = Ecclesiastical History of Bede
HB = Historia Britonum of Nennius/Mark
HRB = Geoffrey of Monmouth
ND = Notita Digitatum

OEC = Old English Chronicles
R of C = Richard of Cirencester
SS = Saxon Shore

Wiki = Wikipedia
 

Appendix/Addenda.

Arthur's battles might have been somewhere in the following:

The westward limit of Anglo-Saxon cemeteries is only (at most) about 60 miles further west in the 7th century than it was in the early 5th (Halsall).
1st victory of Ambrosius between 429-450/456 (EH?)
Bede jumps 447/456 (to 565) to 596 (EH).
Jutish phase 450-500.
Increasing Saxon settlement ca 452-453.
Series of conflicts 455-519 (ASC, Brynjulfson).
Britons migrate to Brittany 458-460/480 (Evans)?
Saxon victories largely confined to coastal areas ca 460 (ASC).
Period of minimal Saxon activity 466-73.
British Recovery 473-517 (Ashe).
Only landings on the coast 488-547 (ASC).
50 yrs relative peace 488/496/503/504-547/570/577 (Evans, Wiki, Doyle).
ASC silent on Kent 488-565 (ASC).
Sussex disappears from the records 490-685.
Gap between Bretwaldas 491-560.
Saxons take 57 yrs to advance 25 miles 495-552 (ASC).
"Saxon advance halted ca 496-550".
"No archaeological evidence for occupation by Anglo-Saxons in that area of Sussex between the 5th and 8th century."
The Saxons were at Dorset's borders at beginning of 6th cent.
"gap in Gildas 500-550" (Carroll)?
Angles & Frisians emigrate to Continent 510-555/534-548/1st half 6th c. (Procopius).
Frankish influence 510-570/ear-late 6th.
We hear no more of Kentish dynasty of kings 512(-552/560).
No gains gap 516-552 (ASC).
"Essex not recorded king until Aescwine 527" or 604 (ASC)?
Mass migration of Celtic monks to Brittany ca 530-540.
Anderida appears to have been resettled by about the middle of the 6th century by a Saxon community.
Conflict between West Saxons & Kentish 568 (ASC).
Anglian slaves sold at Rome 580 (Gregory).
West Saxon king driven from his kingdom at Woddesbeorg 591/592 (ASC).
"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." (Brynjulfson.)
Romano-British fields in Hampshire, Buckinghamshire, & Essex were ploughed into the 7th century.
 

Following are candidate matches in the ASC & AC for the 12 battles of Arthur in the HB of Nennius. The most likely matches are asterisked.

Glein (Great Yarmouth?) - Aegelsthrep/Agaelesthrep/"Aylesford" 455?* Cerdicshore 495/514 (ASC, GYAM)? Glewancester 577? Glannauc 629?

Dubglas/Linnuis (Othona/Ludanbyrg?) - "Thanet"? Crecganford/Lundenbyrg "Crayford/London" 457?*

Bassas "shallow" (Reculver?) - "Thanet"?* Ebissa? Epsford 455?* Wippedsfleot 465?* Cerdicesford/Avene 519? Bensington 571? Bass 669? Reculver 690?

Celidon (Kit's Coty/Coldrum? Weald in Caesar's invasion) - "Kit's Coty, Aylesford" 455?* "Crayford/Dart/London" 457? "no record" (HB/HRB)?* unnamed/fled like fire 473?* Andredesleaga 477?* Andred 490? Netley/Cerdicesford 508? Cerdicesleag 527?* "Aylesbury" 571? Arthuret/Merlin 573? Fethanleag 584? Wigracester "white town in green woodland" 584?

Castellum Guinnion (white, Badon in AC, Dover?) - Derguentid? "Thanet"?* Benedict shone 482? Andredescester 490? Wihtgarasburh 530? Wight 534? Wihtgarasburh 544? Martii 538? Bamburgh-castle 547? Wibbandune 568?* Egonesham 571? Arthuret/Gwendolau/Merlin 573?* Dyrham 577? Wigracester "white town in green woodland" 584?* Wight/Ashdown 661? sea/Centwin 681? Kent & Wight 686? Michael on Mt Gargano 718?

Legionis ("2nd Rome", Rutupi/Richborough/Gawain?) - stone on Gallic seashore?* "Thanet"?* city of Andred 490? Portsmouth/Llongborth 501?* Natanleod 508?* Iulius 540? Liganburh 571? Eliffer 573?* Wigracester "white town in green woodland" 584?* city of the legion 601? "Chester" 607/613? Maserfield/August 642? Campus Gaius 656? "Rome" 688? Usk 728?

Tribruit (Lemanis/Lympne?) - Pen/Parret 658?* Trent 679? sea 681?

Agned/Bregion (Anderida/Pevesney?) - Andredesleag 477? Andredescester 490?* Egonesham 571? "Aylesbury" 571? Pen 658?* Sussex 661?* Bedwin/Agatho 675?* Bregowin 759?

Badon (Thanet mentioned in aftermath in HRB, Portchester?) - Halleluyah 429? "Thanet"?* Benedict shone 482? Benedict ascended 509? Badon 516? Cerdic died 534? Bebbanburh 547? Badon 554 (Hergest)? Beranbury 556? Wibbandune 568?* synod of Victory 569?* Bath 577? Woddesbeorg 592?* Beandune 614? Bardney/Barnburgh 642? Bradford 652? Pontesbury/Ashdown/Wight 661?* Badon 665?* Bedwin 675?* Wight 686? Llongborth/Devon 710?

Camlan/Avalon - Natanleod 508?* Benedict ascended 509? Camlan 537? Camlan 542? court of Rhos 547? Gabran 558? Arthuret 573?* civil war 568? Bedcanford 571?* Woddesbeorg 592?* Cantscaul 631?* Bardney 642? Avon 652? Morgan dies 655? Glastonbury 688?

Arthur - Atilla 443? Vortigern British king 449?* Ethelbert?* Ethelric 588-593? Aethan 603? Garth Maelog 722? Arthgen rex 807?

Britons vs Saxons - Jutes vs Saxons 449? Kentish vs Saxons 568?* vs South Saxons 607?* East Anglia vs Northumbria, Northumbria vs Kent, vs Ethelings 617?*

---------

I'll just append the note on Badon's date and location which I've started working on:

Name Bath / Bado/Badeu / Badon/Baddon/Vadon/Faddon / Badonis/Hadonis / Badonic / Badonicus / *Badonbyrig / Kaerbadum / Baddesdown/Bannesdown / Bath-hill (DEB, HB, EH, HRB, Rhonabwy, Camden, Wynn, Jackson):
Badrig/Patrick.
Badarn/Padarn/Patern/Paternus of Gwenedeg/Vannes.
Beandune/Bampton 614 (Ethelwerd, ASC).
Brunandune/Brunanburh (Ethelwerd).
Braddon Hill, Dover.
There is a Bath area in map of Roman Dover.
Branodunum/Brancaster (ND)?
Braydon Water (Great Yarmouth)?
Bradwell/Ithancester?
Adurni (Portchester, ND)?
Abaddon (Apocalypse/Revelation, Bible).
Wibbandune/Wimbledon 568 (ASC).
Arthur of Bradley (ballad).
Benedict Biscop Baducing is a similar B- name (ASC)?
Woddesbeorg 591/592 (ASC). (Compare Woden/Wodan & Badon/Vadon?)
Beadanhead/Bedwin 675 (Ethelwerd, ASC).
Cunedda vs Bethan/Liethali (HB)?
Baithene son of Aedan?
Badbury Rings.
Bebbanburh/Bamburgh 547 (ASC).
Beranbury 556 (ASC, d/r interchange?)
Boadicea?
Bradwen (Cattraeth, Gododdin)?
Highland of Adowyn/Adoen / Adonwy / Adan (Gododdin)?
Boduni/Dobuni?
Badr 624 (Muslim).
Ysbaddaden (C&O).
Atilla & baedon/baedan 443 (ASC).
Bath 577 (ASC).
Baodan/Baetan/Baitan son of MacErca 566/567/581.
Fiachna son of Baetan 623 (Annals of Ulster).
Spanish queen Badda/Baddo 589/587/586.
St Bothan, St Bathan, St Baithan, St Baithen, St Baiton, St Baothin.
Bdora/Bodotria.
Bodgu?
Bishop Baithanus 640 (Bede).

Date 40/43/44/45 yrs or 1 generation (DEB):
It is not known for sure whether the 44 yrs was from the arrival of the Saxons to Badon, or from Badon to Gildas'writing the DEB, and whether Gildas' birthday was the date of the arrival of the Saxons or the date of Badon.
Gildas' dates range in early sources is 421-512/572.
40 yrs alarm after Maximus (HB).
40 days & nights Germanus (HB).
Halleluyah Victory curbed invasion threat for a generation (EH).
16 + 25 yrs Patrick (HB)?
40 yrs Patrick (HB).
85 (2 x 40) yrs Patrick (HB).
120 (3 x 40) yrs Patrick (HB).
40 days & nights Patrick/Moses (HB)
Patrick's pope was Celestine who is the 43rd pope.
405 yrs nativity of Lord to coming of Patrick & 40 yrs death of Patrick to death of Bridget (HB).
40 yrs death of Patrick to death of Bridget & 4 yrs birth of Columba to death of Bridget (HB).
Vortimer's battles in section 44 of the HB.
40 days Rum map Urbgen (HB).
44 yrs easter 438 to Badon 482 (McCarthy & OCroinin)?
44 yrs arrival of Saxons 447/449 to Badon 491/492/493 (Bede)?
Columba "dove" & Iona "dove" linked with Jonah "dove" who is linked with 40 days in the Bible.
77 yrs old minus 32 yrs = 43 yrs old Columba (ASC 560 entry).
43 yrs Columba 521 (AC) to Columba/Ida 560/565 (ASC).
128 (3 x 43) yrs Vortigern to Badon (Hergest).
444th yr Scots & Picts (Ethelwerd).
Cadwallon 443 ad in one source.
Cunedda 443/445/446 ad in one source.
Socrates Scholasticus 445 ad.
Emmigration of Angles to the continent 510-555 (Procopius, Evans) matches 44 yrs?
Nynnio ap Erb 555-595 matches 40 yrs.
400 - 4 (HB 66) vs 447 (HB 15, 31, 50) is 43 yrs difference?
Riothamus connected with Euric 440-484 matching 44 yrs.
Riothamus connected with Geatica chapter/section 45.
40 days St Martin (Brewer's).
St Martin died 444 in ASC.
Atilla the Hun 443 ad (ASC).
Higham dates Badon to 430-440.
Theodoret & Evagrius 544 ad.
Pestilence 544 ad (Columba).
Stilicho 4400 (R. of C., Claudian).
Badon 516 to Camlan 537 is 22 yrs (half of 44, AC).
"Great victory of Arthur against Saxons on St David's birthday/day 540/640"?
542 ad Camlan (HRB).
Benedict shines 482 (ASC) + 77 (45 + 32) yrs Columba 560 (ASC)?
Benedict shines 482 (ASC) + 40 yrs = Columba born & Brigit died 521 (AC).
28 yrs Stilicho to Vortigern + 12 yrs to Ambrosius, & 4 yrs Vortigern to Saxons (HB)?
44 yrs from arrival of Saxons (DEB, EH) might connect with 56/66 yrs 448/458-514 of Ethelwerd, and/or the 69 yrs from the arrival of the Saxons to Decius & Valerian in the HB?

Badon was 44 or 150 yrs after the arrival of the Saxons.
The dates for the various invasions of the Saxons are 350, 360 (Germanics, Wiki), 367/368 (Germanics, Theodosius), 380 (SS forts), 397 (Picts/Irish/Saxons), 400 (HB), 4400 (Stilicho vs Saxons, Richard of Cirencester), 406 (Germans in Gaul sever contact between Britain & Rome), 408/410 (attacks by Scots/Picts/Saxons), 421, bef 429 (Germanus), 438 (ACb), 441 (Gallic Chronciles), 443 (ASC), 446, 447 (HB, AC), 447 (180 years before 627, Bede)? 449 (Hengist, ASC, Ethelwerd), 449-456 (Bede), 469 (ACb), 473 (Brynjulfson), 477 (Aelle, ASC, Ethelwerd), 494/495 (Cerdic, ASC), ca 500 (Northumbrian Angles, Wiki), 501 (Port, ASC, Ethelwerd), 514 (Stuff, ASC, Ethelwerd), before 547 (Ida, ASC), ca 550 (Essex, Wiki).

Birthday of Gildas (DEB):
It is not known for sure whether the 44 yrs was from the arrival of the Saxons to Badon, or from Badon to Gildas'writing the DEB, and whether Gildas' birthday was the date of the arrival of the Saxons or the date of Badon.
Gildas' dates range in early sources is 421-512/572.
Birth of Columba 405 + x + 40 - 4 (HB).
Birth of Columba 521 (AC).
Birth of Columba 560 - 43 = 517 (ASC).
Birth of Brigit 454 (AC).
Birth of David 458 (AC).
"Great victory of Arthur over the Saxons on St David's birthday/day 540/640".
St Patrick propetically foretold St David's birth (HRB).
Gildas met St David's pregnant mother.

840/940/960 slain (HB 946/994):
Battle of Athelstaneford 836.
Natanleod may come from Gwledig Naw Cant Lliwed "ruler of 900 (warrior) companies".
939 ad Brunanburh (Ethelwerd).
2040/2046 slain at Beandune in 614 (Ethelwerd, ASC).

Date 516/518 (AC):
Benedict ascended 509 (ASC).
Gildas wrote/died 512 (W of M).
56/66 yrs 448/458-514 of Ethelwerd.
"Aelle/Alle/Ella died ca 515."
David 10 years under Pol Aurelian 514, David born not later than 514 (Life of David).
Cadwallon 517 ad in one source.
Birth of Columba 560 - 43 = 517 (ASC).
Columba was born 4 yrs before death of Brigit (HB), Brigit died in 521 (AC) which makes Columba born 516.
Beandune/Bampton 614 (Ethelwerd, ASC).
Ethelbert died 616 ad / 5618 am (ASC).
"Arthur invades Eire 519".
Badon 520 (Wood).

Thanet mentioned in Badon aftermath chapter of the HRB. Badon near a flat island in another source:
Vortimer's battle at Thanet (HB, HRB).
Adurni is near Wight which is similar to Thanet.
Our Badon candidate Braddon at Dover is not far from Thanet.

Saxons flee to their ships in Badon aftermath chapter of the HRB, implying Badon was near the coast and implying that he drove them out of Britain. Badon was near the "Severn sea" in the HRB. Badon near a flat island in another source:
Our Badon candidates Braddon/Dover & Adurni are on the coast.
Arthur drove out the pagans at Guinnion in the Irish HB.
Cadwallon "drove the Irish out of Anglesey".
Cunedda expelled the Liethali/Bethan from every part of Britain (HB).
Arthur drove the Saxons out of Britain at Clarence.
The "enemies were routed and driven even to the sea" by Germanus (HB).
The Saxons fled to their ships in Vortimer's 4th battle (HB).
In Vortimer's 3rd & 4th battles the Saxons fled to their ships and betook themselves to Thanet, and sent to Vortigern to desire leave to depart and return to Germany, and they went on board their galleys leaving and returned to Germany (HRB).
Compare St Patrick rid Ireland of serpents/snakes?

128 (3 x 43) yrs Vortigern to Badon (Hergest):
120 yrs Patrick/Moses (HB).
Camlan cw126.
Arthuret yr 128/129.
390-518 (Kamlesh G)?
425/426/428-554 (Hergest, CB, Jones)?
449-577?
Vortigern's dates range is 396-400 (HB), 5658 + 373 + 28 (HB), 426 (Hergest), contemporary of Germanus 429/447 (HB), 447 (HB), 449 (ASC, Ethelwerd), 455 (ASC).

Dux bellorum Arthur leads at Badon in the HB;
Duce Ambrosius seems to lead at Badon in the DEB & HRB bk 4 chap 20:
Germanus was dux proelli, or "Saint Germanus of Auxerre was twice styled dux belli by Bede". Germanus was "was unanimously chosen commander against the Saxons" in the HB.
Ambrosius has dates 429-450/456 (1st victory, Bede)? or in the time of Zeno 474-491 (Bede), or 5658 + 373 + 28 + 12 (HB) or 400 - 4 + 12 (HB), or between 460 & 470/542 (HRB).

Badon near "Winchester" in Welsh Tysilio. Badon of the AC matches Guinnion of the HB:
Adurni is not far from Winchester.
Our Badon candidate Braddon at Dover is also our castellum Guinnion site, and Guinnion may match Guintonhi/Guintruis/Guitguic/"Winchester".

Badon of AC matches Guinnion of HB:
Castellum Guinnion/Gurnion/*Alborum "white fort" 5th/8th of 9/12 might match: St Gwyddno/Goeznovius? Guitolinus vs Ambrosius (HB)? Dover/Braddon (Albion, white, 6th of 9, ND)? Gurthrenion/Gwarthennian of Vortimer & Germanus (HB)? Guinefort? Glasgwin (12 Monasteries list)? Galafort?

Badon is a siege in the DEB, maybe implying defensive fortifications:
Vortimer's battle of Thanet was a siege in the HRB.
Siege Perilous of the Round Table?

Osla/Ossa at Badon (Rhonabwy) & Arthur's 12 battles come immediately after mention of Octa/Otca (HB):
Oslaf/Oslake at Wibbandune 568 (ASC).
Vortimer fought Octa & Ebissa (HRB).
Octa was either the son or grandson of Hengist.
Octa has dates range between 429/460 & 470/542 (HRB)? or 455-488 (ASC), or 512.

Badon occurs in the 12 battles in section 50/56 of the HB:
Ethelbert became king in 560 (ASC).
Ethelbert reigned 56 yrs (560-616, ASC).
Wibbandune 568 (ASC) is 50 yrs after Badon 516 (AC).
56/66 yrs 448/458-514 of Ethelwerd.
Saxons take 57 years to advance to Salisbury 495-552.

Badon may be connected with the 150/300 yrs prophecy of the DEB:
Augustine's prophecy in the ASC 607 entry?
146 yrs Cunedda to Maelgwn (HB)?
St David 146/147 yrs?
Augustine 596 was about the 150th yr from 446 (Bede).
Arthuret yr 152.
330 yrs gap in Edinburgh Chronicle 734-1065.
396 yrs Cerdic 475/477 to Alfred 871 (ASC).
334 yrs Hengist 453 to 787 (Ethelwerd)

Badon is 9th/12th of 9/12 (3 x 3/4) battles sites of Arthur (HB):
Urbgennius of Bath is 9th of 11 consuls (HRB).
Mon/Mona/"Anglesey" is 9th of 9 battle sites of Arthur (PG).
Adurni is 9th of 9 SS forts (ND).
12 yrs Vortigern to Ambrosius vs Guitolinus (HB).
Vortimer's 4 battles and thrice enclosed (HB & HRB).
"3 several battles" of Arthur (HRB).

Dubricius/Dyfrig of Legions was at Badon (HRB):
Dubricius 612 (AC).
Dubris/Dover?
Durovernum/Canterbury?
Durobrivae/Rochester?
Mandubracius of the Trinovantes?
Compare Germanus was at Halleluyah Victory 429.
The city of the legion might be Rutupi/Richborough?
Compare intercession of Columba helped Scots to victory at Bannockburn 1314.

Number 470 slain at Badon in the HRB is 10 more than the 460 slain in the Long Knives massacre and might be a date:
Arthur contemporary of pope Supplicius 468-483 in the HRB.
Riothamus' date is 460/470.
"Ambrosius' battles 460-470".

Possible date of Badon of 482 (easter cycle, McCarthy) or 485 (Snyder) or 485-520 (Wood):
Life of Germanus c 480/480s.
Badon might match Benedict shone 482 (ASC).
"Ambrosius 83 yrs old"?
Arthur contemporary of pope Supplicius 468-483 in the HRB.
"Arthur in yr 454 in Malory = 487 ad"?
Brendan born 484 (Brewer's).
Cayburn battle 488 is similar to Badon & Caliburn?
Patrick 85 yrs (like Moses 80 yrs, HB 55).
"Glein 486" (Wiki).
Hengist died 488. Battle of Cayburn 488 (local tradition).

Some scholars think that Bede's Badon might be the Halleluyah Victory of Germanus in 429, & Higham dates Badon to 430-440:
Arthur and/or Gildas is 421 in the Chronicle of Mt St Michel and/or another source?
Arthur was a contemporary of Gildas who has a maximum dates range of 421-512/572.
Vortigern 426 (Hergest).
Ambrosius's 1st victory 429-450/456 (Bede),
Patrick 428 (AC), 430 (ASC).
Moses appeared in Crete in 431 (ASCe). (Moses = Patrick in HB.)
The 1st victory of Ambrosius has dates 429-450/456 in Bede?
Vortigern's date is 425/426/428 in Hergest.

"Badon date 493 in Bede":
Patrick 492 (Irish Annals).
Michael appeared Mt Gargano 493.

There was a mount/mountain/hill/down at Badon/Baddesdown:
Portsdown Hill at our Badon candidate Portchester?
The hills/downs/heights/cliffs at our Badon candidate Dover?
The mountain in the Pillar of Eliseg?
Dragon's Hill of Natanleod?

Badon was a victory of Arthur over the Saxons:
Ceawlin was driven from his kingdom at Woddesbeorg 591/592 (ASC).
Synod of Victory 569 (AC) after Wibbandune 568 (ASC)?
"Great victory of Arthur over the Saxons on St David's birthday/day 540/640"?
Halleluyah Victory 429.
St Patrick associated with Victoricus.
1st victory of Ambrosius (Bede)?
"Benedict shines in the world" 482 (ASC)?
"Benedict ascended" 509 (ASC)?

Badon 554 (Hergest):
Relics of St Patrick 553 (60 yrs later, Irish Annals).
Sarum 552 and/or Beranbury 556 (ASC)?
The 2nd battle of Badon 634/665 (AC) is roughly 100/110/111 yrs after 554.

Some think that the 2nd battle of Badon might have been in the same place as the 1st battle of Badon:
Badon 2 & easter 665 (AC) has been linked with either Pontesbury & easter 661 (ASC) or Luith Feirn/Fortrenn 664 (Ulster) or Bedwin 675 (ASC).

Arthur carried the image of Mary & cross of Christ at Guinnion &/or Badon (HB & AC):
Santa Maria de Bretona was a Celtic bishopric from ca 569 (Galicia).
Our Badon 1 site Dover/Guinnion has two churches of St Mary in Castro and St Mary .... Sources say St Mary in Castro may date to as early as ca 600 ad.
St Mary's Reculver.
Our Badon 2 site Adurni/Portchester also has a St Mary's parish church in it.
Bitterne has St Marys (dating to at least 690-700)?
There is a 'St Mary Bourne' near Calleva and/or Adurni?
"Winchester, a lofty tower ... founded in honour of Mary" in 908

Guinnion (HB) or Badon (HB, AC) was Arthur's greatest battle in his 12 battles:
The name of St Martin le Grand of Dover might relate to Arthur's greatest battle and/or his 12 battles? (Martin = Mars = war god.)
St Martin's Canterbury?
"St Martin's London" (HRB)?
St Martin died 444 (ASC)?
Calends Martii 538 (ASC)?
Martianus 538?
"Great victory of Arthur on St David's Day (1st of March) 540/640"?
St Martin's Hwiterne long before 560 (ASC)?
Martin Aureo 561?
St Martin of Galicia died 580?
Pope Martin 649-655?
Mt St Michel?
St Michael of Gargano 493? (Michael warrior angel in bible.)

Badon yr 71/72 in the AC:
69 yrs from the arrival of the Saxons to Decius & Valerian (HB)?
Bonedd y Saint 70/71?
Cissa 72/76/89/90 yrs old (Nothgyth Quest).
Gildas dies in 572 (AC).

Caer Odor & Odor Nant y Badd or Nant Badon &/or river Badon/Avon (24 kings doc, CB):
Adurni?
Othona?
Mantuantonis/Mutu-antonis (Ravenna cosmography 69)?
The river Antona at Winchester?

Alternative name of Solsbury for Badon/Bath (HRB):
Our Badon candidate Portchester is in the Solent.
Badon is linked with Brunanburh by Nennius, and some think Brunanburh was in the Solway area.
Some have Badon near Sarum/Salisbury.
Silbury Hill?
Sulis Minerva?

Arthur and/or his battle of Badon have a dates range in early traditional and modern scholarly sources of 3349 bc (Waddell), Ursus 776-742 bc (me), Deoartavo(i)s 47-67 (me), 180 (Arthur, Infopedia), 350/383 (Morris)? 421 (Arthur &/or Gildas, CMSM &/or another source)? contemporary of Gildas 421-512/572 (Sts Lives, DEB), 429 (Badon thought by some to match the Halleluyah Victory in Bede's EH), 430-440 (Badon, Higham), 450/454 (Malory), not 452 (no Arthur, Gallic chronicles), 459-475 (Albericus), during pope Hilarius 461 (Salzbury Annals, Polonius, Preis), during Aegidius 461-464 (Guise), during pope Supplicius 468-483 (HRB), 470 (number slain at Badon in HRB thought by some to be a date), 482 (Badon, McCarthy & OCroinin), 485 (Badon, Snyder), 485-520 (Wood), 487 ad (454 yrs Malory), 490s (Badon, Wood), 492/493 (Badon, "Bede")? 492/493-516 (Badon, Jackson, Evans, Cooper), 494-497 (Badon, Morris), contemp of Cerdic 494/495-516/534 (HRB), 496/497 (Badon, Wiki), 499-511/518 (Badon, Brynjulfson), 500 (Badon, avg, Jackson, Wiki, Dumville), 501 (DEB, Evans), not 511 (no Arthur, Gallic chronicles), 516/518 (Badon, AC, Ashe), 519 (Arthur subdues Ireland), 537/539 (Camlan, AC/WA), 540 (great victory), 542 (Camlan, HRB, Stow & Warner), 546 (Badon, AC), before Ida 547-560/584 (12 battles, HB), 554 (Badon, Hergest), 566/567 (Baodan/Baetan/Baitan as Badon), "abdicated in 574 (541 yrs after the crucifiction)", 576 (Camlan, Hergest), 580 (Simon Stirling), 582/586/588 (Ardrey), 589/587/586 (queen Badda/Baddo as Badon), 631-650 (Arthus, Swedish king list), 634 (Badon 2, ACb), 640 (great victory), 650 (Arthur, Wace, Morris), 665 (Badon 2, AC), 700 (Arthur, Infopedia), 807 (Arthgen, AC, Evans, me), 940 (number slain in HB as date)? Alan of Brittany (Zoetropo).
We can see from all of the early traditional ones that Arthur must have been between 421 and 584, while a 2nd Arthur may have been around in 640-650.

We will just append a list of dates ranges for persons who may be connected with Arthur &/or Badon.

Alban: Ialebion 1758-1739, Albyne 1600/1560 bc, Labienus? 209? d 283/287 (ASC), 304/4304 (R of C), Germanus 429/447, Ailbe 527, synod Alba 544, Albinus 550.

Andrew:

Andred: 477 (ASC), Cayburn 488 (local tradition), 490/491 (ASC), 756.

Agatha/Agatho: 675 (ASC).

Agnes:

Aelle/Alle/Ella: Halleluyah victory 429? came 477 ASC, 490 ASC, d c 515, r 560 ASC, Alleuia 580 (Gregory), d 588 ASC, Alleuia (Augustine).

Adomnan: d 704 (AC).

Aedan: 582 (A of C), fought 603 ASC, d 607 AC, d 651 ASC.

Arviragus: 17/46/47.

Arthur: 3349 bc (Waddell), Ursus 776 bc? Deoratavois 47-67? LAC 180 (Infopedia), gen Ursicinus 349-359? 350/383 (Morris)? Ursinus 366? 421 (CMSM)? Ursus 422? 450/454 (Malory), not mentioned 452 (Gallic), "b 465"? 470 (HRB)? no mention 511 (Gallic), 516 (AC), invades Eire 519, 537 (AC), 540 (SatW)? 542 (HRB), 554 (Hergest), Arthari 586? Arthus 631-650 (Swedish)? 640 (SatW)? 650 (Wace, Morris), 700 (Infopedia).

Arthur: 22 yrs.

Arthuret: 573 (AC) 593 (Hergest).

Arthuret: yr 10 / 128/129 / 152.

Anmericus: 548-551, 566-569, 573-576.

Ambrosius/Aurelius: 1st victory 429-450/456 (Bede), 455 ("ASC", Brynjulfson), c 460 (Brynjulfson), "Ambrosius' battles 460-470", 467 ("AC", Brynjulfson), 479 (major chronicle annals, Wiki), Pol Aurelian synod c 545? Pol Aurelian de Leon d 575?

Ambrosius: 83 yrs old, AC 100 yrs.

Atilla: 434-453, war 443 (ASC).

Amal: 530.

Brendan: b 484 (Brewer's), d 574 (AC), d 577 (Brewer's).

Benedict: shone 482 (ASC), d 509 (ASC), rule 529 (Pears, Parker), d 536 (M of W), biscop 628-689/690.

Benedict: 54 yrs 482-536?

Benignus: d 468 (AC).

Beli/Heli/Eli/Ely: 401 bc, 58 bc, Cymbeline 4 bc, son d 613/616 (AC), d 627 (AC), d 722 (AC).

Brigit: d 405 + x + 40 (HB), b 454 (AC), d 521 (AC).

Badon: 429 (Bede)? 430 (Higham), 482, 485 (Snyder), 493 (Bede)? 516 (AC), 520 (Wood).

Badon: 128 yrs Vortigern to Badon, 44 yrs arrival Saxons to Badon (DEB, EH)? 72 yrs arrival Saxons to Badon, 150 yrs arival Saxons to Badon? 10/44 yrs Badon to DEB, 22 yrs Badon to Camlan.

Brocmail: d 607 (ASC), 613/616, d 662 (AC).

Birinus: baptised 635 ASC, d 650 ASC.

Bebba: 547 ASC.

Bass: at Reculver 669 ASC.

Botolph: 654 ASC.

Beda/Bieda: came 501 ASC.

Boniface:

Cerdic: arrived 495 (ASC), ford 508 ASC, shore 514 ASC, r/ford 519 ASC, leaga 527 ASC, d 534 (ASC), d 616/619 (AC), d 798 (AC).

Cerdic: 514 is the 56th/66th yr (Ethelwerd).

Cerdicshore: 495, 514.

Cerdicsford: 508, 519.

Cutha/Cuthulf/Cuthwin: 568 ASC 571 ASC, 577 ASC, d 584 ASC.

Cynog: d 606 (AC).

Columba: b 405 + x + 40 - 4 (HB), b 517 (ASC), b 521 (AC), pestilence 544, came 560 (ASC), to Britain 562/563 (AC), came 565 (ASC), d 594/595 (AC), life 650 (Adomnan).

Columba: 45 + 32 = 77 (ASC).

Constantine: Condida 571/577 (ASC)? 589 (AC).

Cross: chronicle 734-1065.

Cattraeth/Eidyn/Gododin: 538, 570, 596 (Wiki), 598 (Wiki), 600 (Wiki), 638 (Wiki), 668 (Ulster).

Caesar: 60 bc, 55 bc, 47 bc, daughter 17ad (24 kings).

Cynric: came 495 ASC, r 534 ASC.

Ceawlin: fought 556 ASC, r 560 ASC, d 593 ASC.

Ceolric: 591 ASC.

Conmail: d 577 ASC.

Condida: d 577 ASC.

Cunedda: 328-389, ear 5th c, 443/446.

Cadwallon: 55 443-517, 629 (AC), d 689.

Celestine: 429/430.

Daniel: d 584 (AC).

David: b 458 (AC), b not later than 514 (Life of David), St David's 519/6th cent-1087, TyGwyn 527/528, day 540? d 544 (Usher), synod Llanddewi 545, 580s (Tigernach), buried by orders of Maelgwn late 6th cent (HRB), d in reign of Constantine, d 600/601 (AC, Brewer's), field of Leeks 633, day 640 (SatW)? St David's burnt 645 (AC).

David: 32 yrs, 65 yrs, 100 yrs, 146/147 yrs.

Dubricius: d 612 AC.

Dionysius E...: 527 (Playfair), 532, replaced 1752.

Easter: 438, 453 (AC), 532, 661 (ASC), 665 (AC).

Easter: 84 yrs, 44 yrs, 532.

Evaristus: 79 (Arundel, OEC), 97/99-105/107.

Eleutherius: 156 (HRB), 4160 (R of C), 161 (Arundel, OEC), 167 (ASC), 174/175, 189 (ASC).

Ethelbert: b 552 (ASC), r 560 (ASC), battle 568 (ASC), r 594 (AC), d 616 (ASC), 5618 am (ASC).

Ethelbert: 32nd yr (ASC), 53/56 yrs (ASC).

Ethelings: 617.

Esc: r 455 ASC, r 488.

Ebur: b 150/151 (AC), d 501 (AC).

Elvod 613, 755 (HB apology/prologue footnote in OEC), 768 (AC).

Finian:

Farimail: d 577 ASC.

George: d 300 (Brewer's), Dragon's Hill 508? adopted 1098.

Glastonbury: 688/7th cent (ASC), 1184/1539.

Germanus: Alleuia victory 429, 2nd visit 447, died 448, life c 480/480s.

Gildas: 421 (CMSM or another source)? b not later than 498 (Life of David), born "c 500", "gap in Gildas 500-550" (Carroll), wrote/died 512 (W of M), wrote 546 (Habington, HB 31), to Eire 565 (AC), d 570/572 (AC, Irish, Wiki), Hilda d 680 (ASC)?

Gildas: 44/150 yrs, 10/44 yrs, wrote 29/44/53 yrs (Evans), d 54/69/78 yrs (Evans).

Hengist: Hergest? came 449 ASC, d 488, battle 835 ASC.

Horsa: came 449 ASC, d 455 ASC.

Ida: 547 (ASC), 560.

Iago: d 613 AC, laid waste 952 AC.

Julius: 540 ASC.

Judoc: 903 (ASC).

Kentigern/Mungo: d 612 (AC).

Laurentius: 616 ASC.

Leo: synod 439 (ASCe), 453/455 (AC).

Llongborth: 500/501/508, 710/712.

Lucius: 156/167/189, LAC?

LAC:

Lucius Tiberius/Hiberius: LAC? Lucerius 469-70? *

Martin: b 371 (Brewer's), d 400 (Brewer's), d 444 (ASC), calends Martii 538 (ASC), church long before 560 (ASC), Aureo 561, d 580 (Galicia), Martinus 641, Pope Martin 649-655, at St Martin's 1061.

Mary: 569 (Bretona), 600 (Dover), 690-700 (Bitterne), 694 (ASC), 908 (Winchester, Ethelwerd), 1088.

Michael: 421 (CMSM)? Gargano 493, consul 538? consecration 718 (AC).

Mildrid:

Maximus: 381/383 (ASC), 422?

Maelgwn: d 547/549 (AC), Mailcun 559? Coinmail 571/577 (ASC)? d 581/586, succeeded 590.

Maelgwn: yr 10? yr 146 (HB).

Mela: came 501 ASC.

Mellitus: 604 ASC, d 624 ASC.

Mauricius: 583 (ASC).

Marcian: r 449 ASC.

Marcus: 406.

Mark:

Nennius: 55 bc, Nemuivus found at Bodleian (5th-8th cents), 542/547 (HB)? Nynnio ap Erb 555-595? Ninnian long before 560 (ASC)? 613 (Nennius & Elvod), "evidence vatican ms HB old as 674", that he had/used earlier sources dating ca 679/680, late 7th cent (Brewer's/Cooper), 796 (OEC), "claims of Mark/Marcus the Anachoret 822 to authorship of HB", 858 (421 + 428/438, Mermenus, HB), 946 (HB), 976 (HB), 984 (HB date of some), 989 (447 + 542, HB), 994 (447 + 547, HB, OEC), edited 10th cent (Mark's date, Gunn), 1071 (Irish HB)? Dumville on Nennius not before 12th century,  "12th cent historians refer to HB under name of Gildas / ascribed it to Gildas".

Ninnian: long before 560 (ASC).

Nicholas: at council 325 (Brewer's), 343 (ASC).

Neot: chronicle 914.

Natanleod: d 508 ASC.

ND 395/400s/420/420s/428, until 15th c/1542/16th c/before 1672 (Speyer).

Oslake: 568 ASC.

Palladius: sent 429 (ASC), 430 (Ethelwerd).

Patrick: 365 books? b 387/389 (Brewer's), 403 (popular writers & folk piety), came 405 (HB), 421 (HB)? left 428 (AC), sent 429/430 (ASC), arrived/landed 432 (Irish Annals, Brewer's), 433 (Life of Patrick), arrival 438 (HB), d 457 (AC), consul 459? d 461/462 (Irish Annals, Brewer's), 492 (Irish Annals), letter to Coroticus 496-508, consul 500? relics 553 (60 yrs later, Irish Annals).

Patrick: x yrs, slave 6/7 (HB), captive/freed 16/17 (HB), continued great while in Rome, consecrated 25 (HB), 30 yrs (AC), (16 + 25 = 40?) taught 40 (HB), (Irish baptised in 5th yr of Logiore,) apostle of Irish 85 (HB), died 120 yo (HB), 60 yrs after (Irish), (+ x yrs) + 7 yrs to coming Lord / Judgement.

Paterius: 443.

Pedridan/Penda: 658 ASC.

Paulinus: 534, converted 601 ASC, invested 625 ASC, baptised 627 ASC, d 644 ASC.

Paulus: 496/498/512/517/518.

Count Paul: 460/470?

Pol Aurelian: David 10 years under Pol 514, synod c 545, d 575.

Pabo: son died 595 AC.

Peter: 616 (ASC), 626 (ASC), 643 (ASC), 655/656 (ASC), 675 (ASC), 686 (ASC), 688 (ASC).

Petrus: 406/433/443/489/504/516/521/533/534/540.

Porta: came 501 ASC.

Riothamus: 460, 470.

Rhun: baptised 626 AC.

Redwald: 617 ASC.

Rutupi/Richborough: built 277-285 or 305 or ca 395, legio Augusta garrison at/to 305, legion 2 Augusta at 395/400s/420/420s/428 (ND), church built end 4th or beg 5th cent, large popn ear 5th cent.

SS: forts ca 270/293, 360 (Wiki), 368 (Theodosius)? 380, 395/400s/420/420s/428 (ND), 452 (revolt, Wiki).

Severus: 189/207, 447, 632.

Supplicius: 468-483.

Sutton Hoo: 491-612/620(-"660").

Stuff: came/fought 514 ASC, 534 ASC.

Theodosius: count 367/369, r 423 ASC.

Tewdrig: 584, 630.

Uriens: 567, 575 (Wiki), 590, after 596-600 (Wiki).

Victor:

Valentinian: r 449 ASC.

Vortigern: 396-400 (HB 66), 426 (Hergest), invited 447/449 HB/ASC.

Wihtgar: came/fought 514 ASC, taken 530 ASC, given 534 ASC, d 544 ASC.

Wipped: came 449 ASC, Epsford 455? d 465 ASC, Wibbandune 568 (ASC)?