A Prince. The son of Alfonso, Alberdure is in love with Hyanthe. He is given wine by Flores and Cornelia laced with a drug provided by Dodypoll, and the drug drives Alberdure mad. He hallucinates, talks wildly, runs about, and eventually throws himself in a river. The cold water cures his madness. Meeting the Peasant, he convinces him to exchange clothes and, thus disguised, tests the loyalty of his friend Leander and his beloved Hyanthe. Finding them loyal he quickly reveals his true identity to them and hides himself with Hyanthe in Hardenbergh's house. He is reunited with his father by Leander and, eventually is given permission to marry Hyanthe.
ALBERTUS
The name of the Merchant. He is in love with Cornelia and a rival to Dodypoll. After Flores is disgraced, the Merchant renounces his interest in Cornelia. Later, the Merchant convinces Dodypoll that Flores has hatched a plot against him in order to make Dodypoll embarrass himself before the Duke. The Merchant is only sometimes referred to as Albertus.
ALFONSO
The Duke of Saxony and father of Alberdure. Alfonso is betrothed to Katherine, and though he is in love with Hyanthe, he claims he is still obligated to honour his engagement. Nevertheless, when it is demanded of him why he delays the marriage, he continues to make excuses and continues to pursue Hyanthe. Seeing his son mad and Hyanthe apparently in love with him, Alfonso claims that Hyanthe has enchanted Alberdure and orders her imprisoned - all in an effort to force her to change her affections. When Alfonso learns that Alberdure has been driven mad by the drug given to him by Flores, and later believes him to be dead, he vows that he would give up his love for Hyanthe if he could be reunited with his son. Soon after, Alberdure, still alive, appears in court, but Alfonso is angry at having been tricked and insists on marrying Hyanthe despite his previous pledge. When Katherine and Constantine arrive to demand an explanation of Alfonso's behavior, Alfonso changes his position again, insisting he has no love for Hyanthe and that she is his son's.
CASSIMERE
Father of Hyanthe. Cassimere is a great admirer of the Jeweler Flores. When Flores is disgraced and Cornelia's other suitors abandon her, Cassimere marries Cornelia himself.
CONSTANTINE
The Duke of Brunswick and brother to Katherine. When his ambassador is put off, he and Katherine travel to Saxony in person to demand of Alfonso why the marriage Katherine has been repeatedly delayed.
CORNELIA
In love with Alberdure. She reluctantly agrees to drug Alberdure's wine in an effort to make him love her. When Alberdure comes to dine at her father's house she gives him a jewel, and later gives him the drugged wine. When the plot is uncovered, and Cornelia's suitors abandon her, she despairs until the noble Cassimere agrees to marry her.
CORNELIUS
An unconvincing disguise assumed by Lassinbergh.
DOCTOR DODYPOLL
A doctor, apparently French, in love with Cornelia. He provides Flores with a powder meant to act as a love potion. When the powder drives Alberdure mad, Dodypoll explains to Alfonso the nature of Alberdure's madness, but claims that it was not due to the powder itself but to Flores' and Cornelia's overly large dose of it. After Flores is disgraced, Dodypoll renounces his interest in Cornelia. Later, the Merchant convinces him that Flores has plotted against him and Dodypoll rushes into court, making a fool of himself. "Dodypoll" seems to be an extension of the Doctor's real name, "Dody" by which he is sometimes called.
ENCHANTER
A magician, who both pitying and loving the wronged Lucilia, intercedes on her behalf. He uses his magic to make her forget Lassinbergh and attempts to convince Lucilia that he himself is her beloved. His plans are ruined when Flores happens upon them.
FLORES
A jeweler. Procuring a love potion from Dodypoll, Flores gives it to his favorite daughter Cornelia with instructions that she should administer it to the Prince. Meanwhile he is offended by Lassinbergh's dishonest advances towards his other daughter, Lucilia, and insists that he marry her. Later, he is convinced by the Peasant that there is a store of treasure waiting to be found. In searching for it, he finds Lucilia and Lassinbergh in the spell of the Enchanter and frees them. Flores is arrested when it is revealed his actions led to madness in Alberdure. Later, Flores presents Katherine with a gift, leading Alfonso to forgive all past offenses.
HARDENBERGH
A lord attending Alfonso and father of Leander. When he discovers Lassinbergh and Haunce near the spot where Alberdure had been left, he suspects foul play and arrests them both.
HAUNCE
A witty servant to Flores. Haunce buys clothes from a Peasant who had switched apparel with Alberdure, but refuses to pay for them. With his new clothes, he claims to be a gentleman, but is quickly arrested on suspicion of harming Alberdure. Haunce later appears in court, claiming to be Alberdure since clothes make the man.
HOSCHERMAN
A lord attending Alfonso.
HYANTHE
The daughter of Cassimere. She is in love with Alberdure and beloved by both Alberdure and his father Alfonso. She rejects Alfonso's advances. Later, she is overjoyed to learn that Alberdure has not been drowned and steals away with him. In the end, she is given permission to marry Alberdure.
KATHERINE
Sister to Constantine and betrothed to Alfonso. Traveling to see Alfonso, she happens across her nephew Lassinbergh and his unhappy wife, Lucilia. Seeing her own situation as similar to that of Lucilia, she arranges for Lucilia to accompany her to court, promising to help her. In court, she and her brother convince Alfonso to renounce his love for Hyanthe and agree to proceed with his marriage to Katherine.
LANTSGRAVE
A "ghost character." A nobleman once offended by Alfonso.
LASSINBERGH
A nobleman, the nephew of Katherine, and a painter. He is in love with Lucelia and goes to her father's house disguised as Cornelius, but his disguise fools no one. He denies any wrongdoing with Lucilia and agrees to marry her, but once they are married, Lassinbergh loses interest, becomes melancholy, and departs. He is enchanted by a magician, but when the spell is broken, is still determined to reject Lucilia. Later, awaking and finding Lucilia gone, he has another change of heart and regrets his mistreatment of her. When he appears in court later, he is entirely repentant.
LEANDER
Son of Hardenbergh and friend to Alberdure. He reproaches himself for not remaining with his friend during Alberdure's madness, laments his apparent drowning, and is overjoyed to learn he is still alive. Leander reunites Alberdure with his father.
LUCILIA
The daughter of Flores. She marries Lassinbergh, but is distressed to find that he is unhappy in marriage. When he departs, she desperately follows him. She is briefly ensnared by the Enchanter, but rescued by her father. Still following Lassinbergh, she encounters Katherine whose help in winning back Lassinbergh she reluctantly accepts.
MESSENGER
A messenger to Alfonso.
MOTTO
A servant. He seeks to assist the mad Alberdure. He and Raphe argue over who is responsible for Alberdure's near drowning.
PEASANT
The Peasant is first mistaken by the mad Alberdure for Hyanthe. Later, he convinces Flores he knows of a store of treasure, unwittingly leading Flores to rescue his daughter. Still later, he encounters the cured Alberdure in the woods and is convinced to change clothes with him. The Peasant promptly sells the clothes to Haunce but is not paid for them; nevertheless, he goes off to find Flores, to sell the jewel that he had found in one of Alberdure's pockets.
RAPHE
A servant. He and Motto argue over who is responsible for Alberdure's near drowning.
STRO.
A servant. "Stro." seems to be an abbreviation used in the text, but he is never called by his full name. Possibly the shortened form of the actor's name.
URSULA
A "ghost character." A servant of Dodypoll.
VANDERCLEEVE
Constantine's ambassador. He visits Alfonso to ask why his marriage to Katherine is being delayed but is put off with a bizarre story.