Modern audiences are most likely to encounter Yvain and other Arthurian characters in literature. We read Chretien de Troyes's Yvain or Hartmann von Aue's Iwein, and easily slip into the assumption that during the Middle Ages the title character existed primarily, or even exclusively, in these canonical texts. James A. Rushing, Jr. contends, however, that many times the number of people who heard or read Chretien or Hartmann must have known the Ywain story through the varieties of second-hand narration, hearsay, and conversation that we may call secondary orality. And man...