The Duke of Bridgewater and the King of France are identities proclaimed by two fraudsters encountered by Huckleberry Finn and Jim in Adventures of Huckleberry Finn. The two were fleeing retribution for some frauds of theirs when Tom helped them evade pursuing men and dogs; they apparently did not know each other at the time. The Duke is the first to announce his persona, followed quickly by the King. The fraudsters accompany Huck and Jim for a long distance down the Mississippi River.
The Duke and King did not proclaim those titles to anyone else but Huck, Jim, and one another. They took on a number of other identities for purposes of monetary gain, with varying degrees of success.
- An undisclosed amount of time before meeting Huck and Jim, the Duke dealt in patent medicines, theater (as "the world-renowned Shakespearian tragedian, Garrick the Younger, of Drury Lane, London), mesmerism, phrenology (as "the celebrated Dr. Armand de Montalban, of Paris"), lecturing, dowsing, "dissipating witch spells"; "most anything that comes handy, so it ain't work".
- An undisclosed amount of time before meeting Huck and Jim, the King dealt in laying on of hands and other "doctoring", fortune-telling, and preaching.
- Soon before meeting Huck and Jim, the Duke was selling "an article to take the tartar off the teeth" with the side effect of removing the enamel as well.
- Soon before meeting Huck and Jim, the King was running a temperance revival until it was revealed he privately indulged in the drink.