Connecticut Yankee actually includes an account of slaves violently rising up and killing their owner. Hank isn't there to see it himself, and so it's indirectly narrated afterwards, but he does see and describe the dead man: "I was soon at the slave quarters. Empty--everybody gone! That is, everybody except one body--the slave-master's. It lay there all battered to pulp." The slaves that killed him (including the unrecognized Arthur) are condemned to die by hanging, but during the execution Arthur, Hank and most of the slaves are saved when Launcelot and the other knights ride to the rescue on bicycles. Typical of the novel's ambiguities is what, if anything, this pair of incidents -- a slave revolt and the rescue from lynching -- implies about American race relations.
The Barrett Collection, UVA PS1308 .A1 1889