Thomas
Thomas Becket is the Archbishop of Canterbury and former Chancellor of England. Historically, he stood up against Henry II's demands that the Church subsume its authority to Henry's secular power, and ultimately died for the cause. In the play, he is represented as an overly proud and sanctimonious man who nevertheless transcends his weakness to accept martyrdom as God's will.
Chorus
The chorus of Murder in the Cathedral comprises the women of Canterbury. Poor, common, and plain, these women have lived a difficult but manageable life since Thomas was sent into exile seven years before the play begins. Though they are Catholic and respect the archbishop, they are also worried that his return will bring them a new level of spiritual burden. The play examines the way they come to accept their spiritual responsibilities through the example of Thomas's martyrdom.
Herald
A messenger who brings word that Thomas Becket has returned to England and will soon arrive in Canterbury. He has a premonition that Thomas's return presages violence.
First Priest
A nameless priest of Canterbury, characterized by his excessive mournfulness and worry. He continually sees the situation of Becket's return as one that can bring trouble for his people and their country.
Second Priest
A nameless priest of Canterbury, characterized by his pragmatism. He examines Becket's return based on its political ramifications and notes how Becket's clash with Henry reflects issues of land ownership and power, rather than spiritual dominion.
Third Priest
A nameless priest of Canterbury, characterized by his patience. Whereas the other priests worry about how Becket's return will change their lives, the Third Priest suggests that, as no human can understand the way the universe works, so should they remain patient and allow God to work his will upon the world.
First Tempter
The first man to tempt Thomas identifies himself as Old Tom. He is a friend from Becket's early, carefree days, and he tempts Thomas with the possibility of relinquishing his responsibilities in favor of a more libertine lifestyle.
Second Tempter
The second man to tempt Thomas identifies himself as a political ally from Thomas's days as Chancellor. He tempts Thomas to resume his role as Chancellor, arguing that Thomas could do more good for the poor through secular power than he ever could as a priest.
Third Tempter
Thomas does not know the third tempter, who identifies himself as a simple baron. He tempts Thomas with the possibility of ruling the country via a coalition that would split control between the nominal ruler and the barons.
Fourth Tempter
The Fourth Tempter is unexpected. Using subtle arguments, he tempts Thomas with the possibility of courting martyrdom for the sake of his reputation and glory. His temptation is powerful because it touches on something Thomas has wished in his private moments. By denying this temptation, Thomas prepares himself to accept martyrdom for the right reason.
First Knight
Though none of the four knights is particularly individualized before Becket's murder, the First Knight gives his name as Reginald Fitz Urse afterward when he addresses the audience. He claims he is a not a man of eloquence, and so mostly serves as a narrator during the knights' speeches.
Second Knight
Though none of the four knights is particularly individualized before Becket's murder, the Second Knight is introduced as William de Traci afterward. He presents an emotional argument, asking for pity on the grounds that, though the knights committed the murder, they were "disinterested" and merely did what was necessary for the English people as ordered by their king.
Third Knight
Though none of the four knights is particularly individualized before Becket's murder, the Third Knight is introduced as Hugh de Morville afterward. He presents a long, detailed argument that Becket was guilty of great offenses against the English people, and hence was it legal to murder him.
Fourth Knight
Though none of the four knights is particularly individualized before Becket's murder, the Fourth Knight is introduced as Richard Brito afterward. He presents the most subtle argument, claiming that Becket essentially committed suicide by facilitating his murder, and hence the knights are innocent of the crime.
Henry
King Henry II, though not a speaking character in the play, is a large influence on the action. Historically, he was an impetuous king who wanted to subsume the various factions of English power under the crown; the most contentious of these was the church, led in England by Thomas Becket. The knights arrive in his name, and he is cited frequently by those in the play who try to understand Becket's past and character.
Pope
Though not a speaking character in the play, Pope Alexander figures prominently. Historically, he was protecting Thomas Becket at the time of this play's action, allowing the archbishop to announce excommunications upon the English church. His protection is one of the many barriers between Thomas and Henry, and it gives Thomas a defense against the knights.
