When I first really decided to pin down where Arthur would best fit into the historical timeline, I started with pretty much a “core” timeline of undisputed historical events. As you may have noticed if you’ve seen my timeline on this site, there’s a conspicuous gap between about 400 – 800 A.D. Very, very little was written down, especially in Britain, during this period. What little writing that does survive (that of Gildas, Bede, Nennius, and the ASC) is regarded with a high degree of doubt by historians; unfairly so, in my humble opinion. Most of these sources, to include Geoffrey of Monmouth’s work, actually agree pretty consistently as to the basic sequence of events they cover. Granted, some sources omit details that other sources include, but there’s quite a bit of overlap. What virtually every source was annoyingly vague about was dates! but there is at least one key event that every single source lines up with almost to the year- the arrival of Hengest and Horsa. In every source it’s given as either 447 or 449. From that, I could at least ballpark everything that happened before or after their arrival. So for example, when Bede or Nennius writes that “seven years after the arrival of Hengest and Horsa” Vortimer, Vortigern’s son, breaks their alliance and goes to war against the Saxons, I can now figure that this occurs in about 455. Then I find another source that says Vortigern, Hengest and Horsa fought a war that lasted over twenty years. Now I have another date I can plug in.

Some of these dates line up well, and sources do at least say this or that thing happened X number of years before or after this other thing happened. Other times, especially when I included a lot of Geoffrey’s work, I had to ballpark more events and make a few “if this, then that” assumptions along the line of “assuming Uther had Arthur at about age 25, then he should have been born in about this year…” Then I could look through my timeline, plug in that date, and see how well it meshed with the rest of the events of my timeline, or if it made Uther too old or too young to have done some other thing.

By doing this process over and over, and making adjustments here and there, it allowed me to come up with a detailed timeline spanning from the early 400’s to the mid 500’s. This includes Arthur being born around 482, fighting at Badon Hill in about 510, squarely in the middle of the timeframe most historians think that battle could have occurred, and then dying a couple decades later.