Judge York Leicester Driscoll
Dawson's Landing's chief citizen and a descendent of Virginia's First Families. Having no children of his own, he takes in his nephew, Tom, when his brother Percy dies. Living by a strict code of honor, the Judge fights a duel in his nephew's place, when Tom is too cowardly to defend his honor himself. Though he has little tolerance for Tom's drinking and gambling, and often disinherits the boy due to these vices, deep down he loves his nephew and is always quick to put him back into his will. At the end of the novel, Judge Driscoll is murdered by Tom, as Tom attempts to rob him to get money to pay off his debts.
Mrs. Rachel Pratt
Judge Driscoll's widowed sister. She lives with the Judge and helps him care for Tom after the Judge's wife dies.
Pembroke Howard
A descendent of Virginia's First Families and a close friend of Judge Driscoll. He serves as the Judge's second in the duel against Luigi Capello. After the Judge's murder, he acts as state prosecutor in the criminal trial against Luigi and Angelo.
Colonel Cecil Burleigh Essex
A prominent citizen in Dawson's Landing and a descendent of Virginia's First Families. He dies during the same fall season as Percy Driscoll. Later, it is revealed that he is the father of Roxy's baby
Percy Northumberland Driscoll
Judge Driscoll's brother and Tom's father. He is a descendent of the First Families of Virginia. He has successful land speculations which make him wealthy during his lifetime. But these speculations ultimately fail and when he dies, his debts leave his son a pauper. When his son, Tom, is an infant, Percy cannot tell him apart from his slave Roxy's baby. The only way Percy can distinguish the two children is by their attire.
Roxana (Roxy)
One of Percy Driscoll's slaves. Roxy is charged with caring for her master's son, Tom, along with her own child, Chambers. Fearing that her child will one day grow up and be sold down the river, Roxy decides to switch the babies. Upon Percy Driscoll's death, he grants Roxy her freedom, and she decides to become a chambermaid on a steamboat. Later, she consents to her son selling her back into slavery to help pay off his gambling debts.
David "Pudd'nhead" Wilson
A young lawyer who moves to Dawson's Landing from New York. Shortly after arriving, he hears a dog barking loudly and remarks that he wished he owned half of the dog. When one of the townspeople inquires as to why he wants to own half, he responds so that he can kill his half. As a result of this odd comment, Wilson is labeled a fool and given the nickname Pudd'nhead. He becomes somewhat isolated from the rest of the town and is unable to get his law practice started. His reputation as a fool is only made worse by his bizarre hobbies: palmistry and collecting fingerprints. Despite this reputation, he fosters a friendship with the town's chief citizen, Judge Driscoll, as well as the two Italian twins, Luigi and Angelo. In the end, when Luigi and Angelo are on trial for Judge Driscoll's murder, Wilson serves as their defense attorney. Through his knowledge of fingerprints, he is able to uncover that the usurper, posing as Tom Driscoll, is the true murderer and reveals the slave's deception.
Thomas a Beckett Driscoll (Tom)
Percy Driscoll names his child Tom. However, after Roxy switches the babies, Twain refers to the young usurper (who is really a slave) as "Tom." This false heir, due to his overindulgent upbringing, grows to be spoiled and cruel, particularly to slaves and other blacks. He picks up the habits of drinking and gambling while away at Yale. His gambling gets him into deep debt, and he resorts to robbing the citizens of Dawson's Landing to meet his obligations. When he inadvertently insults Luigi Capello at a meeting of the rum party, he receives a massive kick that launches him into the audience and causes a riot. Tom is too afraid to fight Luigi in a duel, and instead brings assault charges against the Italian. This disgraces Tom's uncle, Judge Driscoll, who lives by a strict code of honor. Tom's uncle thus fights the duel in Tom's place. Desperately needing money to pay off more debts, Tom attempts to rob his own uncle. When his uncle seizes him, Tom stabs him with a knife. Though Luigi and his twin Angelo are initially tried for the murder, Pudd'nhead Wilson reveals to the town that Tom is the real murderer, and is in fact a slave, marauding as Tom Driscoll.
Valet de Chambre (Chambers)
Roxy's son. Roxy switches her child with her master's child, so Twain refers to the true heir as "Chambers." Chambers is raised as a slave, and grows up to be meek and docile, but a strong fighter and good swimmer. Tom forces Chambers to serve as his bodyguard. Chambers is the primary target of Tom's cruelty, who is jealous of the slave's natural physical abilities. After Pudd'nhead Wilson reveals that Chambers is the real Tom Driscoll, Chambers suddenly finds himself free, rich, and white. However, because of his slave upbringing, he does not feel comfortable in the white man's world.
The Widow Cooper (Aunt Patsy)
The Widow Cooper is a citizen of Dawson's Landing who the townspeople affectionately refer to as "Aunt Patsy." She lives with her sons and her daughter, Rowena. To supplement her income, Aunt Patsy puts out an ad that she is renting a room. A set of Italian twins respond to the ad, and their arrival makes Aunt Patsy the talk of the town. She relishes in this momentary fame. Throughout the novel she remains loyal to the twins, and is the only person who comes to visit them in jail, as they are awaiting trial for the murder of Judge Driscoll.
Rowena Cooper
Aunt Patsy's daughter. She is described by Twain as a girl of no consequence. No one is more excited than she is for the arrival of the Italian twins. Like her mother, Rowena cherishes her day of glory and the temporary fame that comes with hosting Luigi and Angelo. We later learn that Tom Driscoll worships Rowena.
Luigi and Angelo Capello
Set of Italian twins who respond to Aunt Patsy's ad and rent a room in her home. Their father was a Florentine nobleman, but because he was on the losing side of a war, the Capello family was forced to flee to Germany. After the death of their parents, Luigi and Angelo were sold into servitude to pay off their parents' debts. They were put to work as attractions in a Berlin museum, where they are not compensated for their labor and must beg for food. However, fluent in four languages and musical prodigies, the twins are able to pull themselves out of this slavery. In Dawson's Landing, they are widely admired, particularly after Luigi honorably engages Judge Driscoll in a duel. However, their reputation is tarnished after Tom spreads rumors that the reward the twins offered for their stolen knife is a hoax, and when Judge Driscoll suggests that Luigi is an assassin. They are accused of murdering Judge Driscoll, and are defended by Pudd'nhead Wilson. After being cleared of the charges, they decide they have had enough of the American West and return to Europe.
Constable Jim Blake
Constable of Dawson's Landing, he is investigating the mysterious robberies. He suspects that an old woman is responsible, since someone saw such a woman coming out of one of the robbed homes, and because Blake himself saw an old lady escaping on the ferry.
