The duke and the dauphin are a duo of grifters who are defined by fraudulence and greed. When they first board Huck and Jim’s raft after escaping from the angry citizens of a nearby river town, they have already begun their next con. They initially pretend not to know each other, and they portray themselves as down-and-out European royals in an attempt to inspire in Huck and Jim a combination of pity and reverence. It doesn’t take long before Huck figures out their ruse, but he and Jim still get swept up in their swindling ways. Together the four characters go from town to town, giving mediocre performances and scamming the locals out of their money. But no amount of failure and village backlash seems to change the ways of the duke and dauphin; they keep doing what they do, no matter the consequences. If anything, failure only increases the intensity of the characters’ greed, which comes to a head in the novel when the dauphin steals Jim away and sells him to Silas and Sally Phelps.
In addition to driving the plot by offering further “adventures” and selling Jim, the duke and the dauphin also serve thematic purposes in the book. First, their greed echoes that of several other unfavorable characters, including Pap and the murderous thieves aboard the wrecked steamboat. This pervasive hunger for money at the expense of others contributes to the book’s overall concern with the corruptness of society. Second, their incessant fraudulence could be understood as an exaggeration of the kind of make-believe that is elsewhere exemplified by Tom Sawyer. Although Tom does not have the same cruel intentions as the duke and the dauphin, he nevertheless engages in fraudulent behavior when he encourages Huck to impersonate him. Tom also puts Jim in unnecessary danger by not informing him of his freedom and instead using the opportunity to fashion an overly complicated escape plot for him. At the end of the book, then, Tom’s penchant for pretend seems to have a dark side that bears a similarity to the fraudulence of the duke and the dauphin.