Flavius and Marullus Tribunes who wish to protect the plebeians from Caesar's tyranny; they break up a crowd of commoners waiting to witness Caesar's triumph and are "put to silence" during the feast of Lupercal for removing ornaments from Caesar's statues.
Julius Caesar A successful military leader who wants the crown of Rome. Unfortunately, he is not the man he used to be and is imperious, easily flattered, and overly ambitious. He is assassinated midway through the play; later, his spirit appears to Brutus at Sardis and also at Philippi.
Casca Witness to Caesar's attempts to manipulate the people of Rome into offering him the crown, he reports the failure to Brutus and Cassius. He joins the conspiracy the night before the assassination and is the first conspirator to stab Caesar.
Calphurnia The wife of Julius Caesar; she urges him to stay at home on the day of the assassination because of the unnatural events of the previous night as well her prophetic dream in which Caesar's body is a fountain of blood.
Marcus Antonius (Mark Antony) He appears first as a confidant and a devoted follower of Caesar, and he offers Caesar a crown during the feast of Lupercal. He has a reputation for sensuous living, but he is also militarily accomplished, politically shrewd, and skilled at oration. He is able to dupe Brutus into allowing him to speak at Caesar's funeral and by his funeral oration to excite the crowd to rebellion. He is one of the triumvirs, and he and Octavius defeat Brutus and Cassius at Philippi.
A soothsayer He warns Caesar during the celebration of the feast of Lupercal to "beware the ides of March." He again warns Caesar as he enters the Senate House.
Marcus Brutus A praetor; that is, a judicial magistrate of Rome. He is widely admired for his noble nature. He joins the conspiracy because he fears that Caesar will become a tyrant, but his idealism causes him to make several poor judgements and impedes his ability to understand those who are less scrupulous than he. Brutus defeats Octavius' forces in the first battle at Philippi, but loses the second battle and commits suicide rather than be taken prisoner.
Cassius The brother-in-law of Brutus and an acute judge of human nature, Cassius organizes the conspiracy against Caesar and recruits Brutus by passionate argument and by deviously placed, forged letters. He argues that Antony should be assassinated along with Caesar, that Antony should not speak at Caesar's funeral, and that he (Cassius) and Brutus should not fight at Philippi, but he eventually defers to Brutus in each instance. He is defeated by Antony at the first battle of Philippi, and he commits suicide when he mistakenly believes that Brutus has been defeated.
Cicero A senator and a famous orator of Rome. He is calm and philosophical when he meets the excited Casca during the night of portentous tumult proceeding the day of the assassination. The triumvirs have him put to death.
Cinna The conspirator who urges Cassius to bring "noble" Brutus into the conspiracy; he assists by placing some of Cassius' forged letters where Brutus will discover them.
Lucius Brutus' young servant; Brutus treats him with understanding, gentleness, and tolerance.
Decius Brutus The conspirator who persuades Caesar to attend the Senate on the day of the ides of March by fabricating a flattering interpretation of Calphurnia's portentous dream and by telling Caesar that the Senate intends to crown him king.
Metellus Cimber The conspirator who attracts Caesar's attention by requesting that his brother's banishment be repealed, allowing the assassins to surround Caesar and thereby giving Casca the opportunity to stab him from behind.
Trebonius The first of the conspirators to second Brutus' argument that Antony be spared, Trebonius lures Antony out of the Senate House so that the other conspirators can kill Caesar without having to fear Antony's intervention. Consequently, he is the only conspirator who does not actually stab Caesar.
Portia The wife of Brutus and the daughter of Marcus Cato. She argues that those familial relationships make her strong enough to conceal Brutus' secrets, but on the morning of the assassination, she is extremely agitated by the fear that she will reveal what Brutus has told her. She commits suicide when she realizes that her husband's fortunes are doomed.
Caius Ligarius No friend of Caesar's, he is inspired by Brutus' nobility to cast off his illness and join the conspirators in the early morning of the ides of March.
Publius An elderly senator who arrives with the conspirators to escort Caesar to the Capitol. He is stunned as he witnesses the assassination. Brutus sends him out to tell the citizens that no one else will be harmed.
Artemidorus He gives Caesar a letter as the emperor enters the Capitol; in the letter, he lists the conspirators by name and indicates that they intend to kill him, but Caesar does not read it.
Popilius Lena The senator who wishes Cassius well in his "enterprise" as Caesar enters the Senate House. This comment intensifies the dramatic tension in the moments immediately prior to the assassination by causing Cassius and Brutus to briefly fear that they have been betrayed.
Cinna the poet On his way to attend Caesar's funeral, he is caught up in the riot caused by Antony's funeral oration. The mob at first confuses him with Cinna the conspirator, but even after they discover their error, they kill him anyway "for his bad verses."
Octavius Caesar The adopted son and heir of Julius Caesar; he is one of the triumvirs who rule following the death of Caesar. He and Antony lead the army that defeats Cassius and Brutus at Philippi.
M. Aemilius Lepidus He joins Antony and Octavius to form the Second Triumvirate to rule the Roman Empire following the assassination of Caesar. He is weak, and Antony uses him essentially to run errands.
Lucilius The officer who impersonates Brutus at the second battle of Philippi and is captured by Antony's soldiers. Antony admires his loyalty to Brutus and thus he protects him, hoping that Lucilius will choose to serve him as loyally as he did Brutus.
Pindarus At Philippi, he erroneously tells his master, Cassius, that the scout Titinius has been captured by the enemy when the scout has actually been greeted by the victorious forces of Brutus. Thinking that all is lost, Cassius decides to die; he has Pindarus kill him with the same sword that he used to help slay Caesar.
Titinius An officer in the army commanded by Cassius and Brutus, he guards the tent at Sardis during the argument between the two generals, and is a scout at Philippi for Cassius. After Cassius commits suicide when he mistakenly believes Titinius to have been taken prisoner by the enemy, Titinius kills himself in emulation of Cassius.
Messala A soldier serving under Brutus and Cassius, Messala gives information concerning the advance of the triumvirs, and he reports Portia's death to Brutus at Sardis. At Philippi, he hears Cassius confess that he believes in omens. Later, he discovers Cassius' body.
Varro and Claudius Servants of Brutus, they spend the night in his tent at Sardis. Neither of them observes the ghost of Caesar that appears to Brutus.
Young Cato The son of Marcus Cato, the brother of Portia, the brother-in-law of Brutus, and a soldier in the army commanded by Brutus and Cassius. He dies during the second battle at Philippi while trying to inspire the army by loudly proclaiming that he is the son of Marcus Cato and that he is still fighting.
Clitus and Dardanius Servants of Brutus, they refuse their master's request at Philippi to kill him.
Volumnius A friend of Brutus and a soldier under his command at Philippi. He refuses to hold a sword for Brutus to impale himself on.
Strato The loyal servant who holds Brutus' sword so that he may commit suicide. Later, he becomes a servant to Octavius.