Sharan Newman has plumbed medieval history--that enormous and dimly known region of time from the fall of Rome to the Renaissance--to serve up two series of novels that deal with the Middle Ages, warts and all. Her "Guinevere" trilogy takes a novel look at the Arthurian legend, from the point of view of Guinevere, his bride, while her "Catherine LeVendeur" mystery series takes a scalpel to the twelfth century through the adventures and investigations of a French woman. "I believe that human beings have changed little emotionally in recorded history," Newman wrote in the Ricardian Register. "Greed, fear, love, hate and revenge are all understandable today. So the reader has something familiar to hold on to while I take them into the medieval permutations of these traits." For Newman, writing historical mysteries "is another way of teaching about a time I love and intend to continue studying for...