Illustration from page 190 of <i>The Boy's King Arthur</i>: "King Mark slew the noble knight Sir Tristram as he sat harping before his lady la Belle Isolde."
<bdi><a href="https://en.wikipedia.org/wiki/en:N._C._Wyeth" class="extiw" title="w:en:N. C. Wyeth"><span title="American illustrator, painter (1882-1945)">N. C. Wyeth</span></a>
</bdi>
1922
<i>The Boy's King Arthur: Sir Thomas Malory's History of King Arthur and His Knights of the Round Table, Edited for Boys by Sidney Lanier</i> (New York, Charles Scribner's Sons, 1922).  Scanned by <a href="//commons.wikimedia.org/wiki/User:Davepape" title="User:Davepape">Dave Pape</a>.