Vincentio: the Duke who authorizes Angelo to rule Venice in his absence though his absence is only a seeming absence as he--the Duke--remains in Venice incognito as Friar Lodowick
Escalus: an ancient lord whose knowledge of statemanship is unparalleled and who is put in charge to the execute the Duke's command which is to fully authorize Angelo as Vienna's proxy ruler
Angelo: a high ranking official who is authorized to act as the Duke's proxy while the Duke is ostensibly away because of his seemingly austere and virtuous reputation
Lucio: a blaspheming, unprincipled dandy and man about town
Gentlemen 1 and 2: men who talk and gossip with Lucio and complain of their illnesses contracted in brothels
Mistress Overdone: the proprietor of a bawdy house (brothel) and a bawd (prostitute) herself
Pompey: a clown and a servant to Mistress Overdone
Claudio: a young nobleman who is Isabel's brother and who is slated to have his head chopped off for unlawful (unmarried) fornication
Provost: an officer of the state who helps Friar Lodowick preserve Claudio's life
Friar Thomas: the friar who provides Vincentio with a friar's robe with which Vincentio will circulate incognito through Vienna
Isabel: a novice in a priory, she is Claudio's sister who attempts to persuade Lord Angelo to commute her brother's death sentence
Francisca: a nun who teaches Isabel that a nun may only speak to a man if she is veiled and in the presence of a prioress or if she is not veiled and she shows her face to a man that she cannot speak and vice-versa
Elbow: a constable who excels at malapropisms
Froth: a foolish gentleman
Juliet: Claudio's lover who has gotten pregnant though she is unwed, landing her in jail
Mariana: Angelo's betrothed who is falsely accused of being unfathful and who is abandoned when her marriage dowry is lost at sea; she is vindicated though when via Vincetio and Isabel's plan she compels Angelo to honor the contract eventually
Abhorson: the executioner who is to carry out Claudio's and Barnardine's death sentences
Friar Peter: a friar who helps the Duke undo Angelo
Barnardine: a prisoner who is perpetually drunk and does not really care if he lives or dies