A Connecticut Yankee in King Arthur's Court

This novel by Twain is one of the early classics of Science Fiction. It tells the story of a Connecticut man from the late 19th century who is transported back in time to the days of Camelot and 5th century England. Twain uses the novel to expound on his beliefs of democracy and to explain the benefits of modern scientific belief. In doing so he likely over exaggerates the superstitiousness of the time period and their lack of knowledge. While it's not the most historically accurate view of the times Twain does an excellent job of portraying a man out of time and the ways in which his knowledge could be used for power or to change the course of history. At times the novel becomes preachy and Twain rails against aristocracy and the church. Overall still a worthwhile read in our current day and age. If you are looking for a little less preaching and a more modern take on the concept of time travel to the Era of Knights I would recommend Timeline by Michael Crichton.