It is 420 AD. The Roman legions left 10 years ago and the barbarians are pounding at the doors. The Angles, Saxons, and Scots-Irish all want a piece of Britannia. The Picts and un-Romanised Welsh are also troublesome neighbours. But the Romano-British kingdoms are fighting back with a combination of ex-Roman troops and men fighting in native styles.
I have written two DBA Arthurian Campaigns based on Martin Smith’s “Arthurian campaign” article in Slingshot (Smith, 2021), itself based on Kaptain Kobold’s solo HoTT campaign (Dux Bellorum). This campaign is “The Legions have Gone” and is set in 420-439 AD. The campaign assumes Arthur existed, was early 5th century, and led Roman troops.