There are thousands of books about the myths and legends surrounding King Arthur. The real question is, how “academic” do you want to get? Let me google that for you. read more
That’s in Latin, but it’s worth learning Latin just for the Arthurian tales and the histories behind them. Or Wace’s “Roman de Brut” (in Gallo, aka “Old French”: you can go to eastern Brittany to learn that language). read more