Well, we plan to make something very accurate. But a big part of arthurian knights existed as historic characters during the Vth-VIth century, they were mostly local kings or princes but not always in the exact timeframe as the Arthur we choose to represent in ATW (there are lot of theories on who was he, we choosed to make him king of Dumnonia/Dyfneint and later Amherawddyr, or High-King of the Britons). Here some:

Gwalchmai, aka Gawain, king of Gododdin.
Urien king of Rheged.
Owein, son of Urien, aka Yvain.
Peredur, aka Perceval, king of Ebrauc
Drystan, aka Tristan, son of Marcus Conomorus, aka King Marc of Cornwall...