Calpurnia is Caesar’s wife, who believes in omens and signs. She warns Caesar against going to the Senate on the Ides of March based on terrible nightmares & reports of many bad omens she has heard. Nevertheless, Caesar’s ambition leads him to disregard her advice.
Brutus is the most complex character in Julius Caesar and the play’s tragic hero. The audience gains insight into his complex motives. He is a powerful public figure, but also as a husband, a master to his servants, a dignified military leader, and a loving friend. His conflicting value systems battle each other on a massive level in Brutus’s mind. Even after the assassination with the other members of the conspiracy, questions remain, in light of his friendship with Caesar. Was the murder a noble, selfless act or proof of a truly evil callous,gross indifference to the ties of friendship and failure to be moved by the power of a truly great man. His rigid idealism is his greatest virtue and his deadliest flaw.
Antony proves strong in the ways that Brutus proves weak.His impulsive nature serves him perfectly,first to persuade the conspirators he is on their side, gaining their mercy, then to persuade the citizens of the conspirators’injustice, gaining their support. Not too scrupulous to stoop to deceit and duplicity, as Brutus claims to be, Antony proves himself an ideal politician, using gestures and skilled rhetoric to his advantage. He knows how to act with each side to know how to gain the most advantage.
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But here is a brief sketch for you:
Calpurnia: Caesar's wife who both worships and fears him. It is Calpurnia who warns her husband that she has seen his statue running with blood. Although she is able to pursuade Caesar to be cautious for a short time, her influence on him is marginal, at best.
Brutus: one of the leaders of the conspiracy against Caesar. He is outwardly such a good guy that he does not garner suspicion. He "sits high in all the people's hearts." His treachery, therefore, is astounding to Caesar, who in his death throws cries out, "Et tu, Brutus?" (You, too?) These words have become synonomous with the betrayal of friends.
Mark Antony: "well beloved of Caesar," "a masker and a reveler," but also a "shrewd contriver." He makes fine speeches and is a brave warrior. It is Mark Antony who will lead the opposition against the conspirators.