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The Holy Grail appears before Arthur’s Round Table; Evrard d’Espinques, manuscript illumination c. 1470. Public domain, via Wikimedia Commons.

Major spoilers throughout the medieval Arthurian stories. One consolidated timeline of events inside the legends of Arthur, Merlin, Guinevere, Lancelot, Morgan, the Ladies of the Lake, the Round Table and the Grail. Now displayed on a proleptic Gregorian / CE calendar, with literary dates and editorial estimates explicitly distinguished.

Calendar anchors and competing chronologies

  • 487 CE · Malory’s Grail: 454 years after the Passion + the medieval age-at-death assumption of 33 = 487, following Andrew Lynch. This is a literary calculation, not historical verification. Lynch’s specific May 17 is a JULIAN date; it has not been inserted as Gregorian May 17. This timeline uses year-level placement only.
  • 516 CE · Badon, Welsh annals: the conventional translated entry; other accounts use 518.
  • 537 CE · Camlann, Welsh annals: other readings/editions use 539. The annal does not say Arthur and Medraut were enemies.
  • 542 CE · Geoffrey: the History’s stated year for Arthur’s removal and Constantine’s succession. It is retained in that tradition, not imposed on Malory.
  • c. 573 CE · woodland Myrddin: the Northern tradition connects his flight with Arfderydd (sometimes dated 575). It remains distinct from the earlier court-adviser reconstruction.

How the estimates work

“c.” means a reconstruction, not a date printed by the author. Every event states its chosen CE year, dating status, model, basis, sources and a broad uncertainty allowance. The ranges are editorial allowances or conflicting textual readings, not statistical confidence intervals. All story events remain legendary; a textual year claim is not proof that it happened.

The Malory model uses the 487 Grail anchor. Earlier events follow his generational and narrative sequence, with assumed round-number placements around 435 for Arthur’s birth, 450 for his accession and 454 for his marriage. Those three years are explicitly editorial, NOT dates attributed to Malory or an external historian. Lancelot’s twenty-four-year confession suggests a rough c. 463 reference point; Galahad’s age gives a conception/birth around 471–472. Internal age and absence clues remain in tension around Lancelot’s madness and are flagged, rather than claimed to be solved.

After 487, the model allows the quest’s more-than-eighteen-month wandering, a year in prison and a year crowned at Sarras, then Perceval’s year and two months before Bors returns. Bors’s return is placed around 493. Later court crises and the foreign war are tentatively distributed through an estimated 498 final battle. 498 is an editorial estimate, not a canonical death date. Lancelot’s subsequent six years of penance plus one year as a priest put Guinevere’s and Lancelot’s deaths around 505 under that same model. Constantine’s accession is placed at Arthur’s fall, not after the later deaths merely because Malory mentions it last. Tristan’s death is placed before the retrospective report, rather than at that report’s chapter position.

The Geoffrey model retains 542 and uses rough backward placements for accession and early wars; it does not borrow Malory’s 487 Grail date. Most independent Welsh and courtly romances have no secure CE year: their c. 500 markers are expressly editorial comparisons within a broad 450–550 setting, not evidence that all these tales occurred in the same year. A tale’s internal relative sequence is preserved in its source and links. The Green Knight’s return is placed one year after his challenge; only that relative interval is textual.

January 1 at midnight UTC is a storage/plotting anchor for a year, never an invented occurrence day. Medieval AD dates are shown by their CE year on the proleptic Gregorian display. There is no claim that medieval narrators used the Gregorian calendar, and no day-level Julian-to-Gregorian conversion is implied. Gap sizes between uncertain estimates should not be read as measured historical intervals. The first-century Grail backstory is far earlier than the main plot: zoom to 430–575 CE for Arthur and Merlin, or 450–505 CE for the Malory model.

Tags, comparisons and sources

Use Separate by tags for malory tradition, welsh tradition, geoffrey tradition, chretien tradition, vulgate tradition, gawain poet, or wolfram tradition, and for individual characters. Markers labeled “c.” and dashed outlines show estimated placements. Exact-looking anchor years still identify literary claims or calculations, never historical certainty.

Purple comparison cards explain multiple lake ladies; the distinct swords; Morgause versus Morgan; the two Elaines and two Iseults; differing Grail objects and heroes; and the final-war variants. The return-belief marker is attached to Arthur’s departure: it does not predict a dated return. Bands are approximate reading guides. Arcs remain undirected narrative or variant connections, not a merged canon or proof of causation; Malory’s old reading order is retained in metadata for reference.

Most story citations go directly to primary chapters in Malory, Geoffrey, the Mabinogion and Chrétien; Rochester’s Camelot Project supplies scholarly context. This is selected medieval mythology, not a comprehensive modern film/TV/game continuity. Text is paraphrased and all existing artwork credits are retained.

Dating references:

Public-domain illustrations

Cover: Evrard d’Espinques, the Grail’s appearance to the Round Table, manuscript illustration, c. 1470. It is a representation of the legend, not a picture of a historical gathering. All selected images are recorded as public domain by Wikimedia Commons; their authors and Commons file/rights pages are credited on the relevant moment or band. No commercial film stills, franchise logos or generated evidence are used.

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