Act I

Main characters

• Julius Caesar – Even though he doesn't appear in the play often, it can be said that the spirit or presence of Caesar runs through the whole play. This influences the decisions and actions of other characters.
  
  
• Marcus Brutus – Brutus is arguably the main character in the play. The conspiracy doesn't form properly until he joins it. We are witnesses to his personal struggles in making that decision and how he lives with the consequences behind it.
  
  
• Cassius – He is the man behind the conspiracy. He is the one who convinces Brutus that Caesar needs to be killed.
  
  
• Mark Antony – Caesar's good friend who is tricked into leaving the Senate before Caesar's murder. He addresses the citizens and turns them against Brutus and Cassius at Caesar's funeral.
  
  
• Octavius Caesar – the nephew of Julius Caesar and his appointed heir. In Roman history Octavius goes on to rule the empire alone as Caesar Augustus.

Act I

Scene i

The tribunes Flavius and Marullus enter the city and are confronted by a group of citizens who are celebrating the triumph of Caesar. There are differences between the speech of the tribunes (who are noble) and the citizens (who are commoners). The citizens, for example, speak in less poetic terms and make several puns.

The tribunes are annoyed by the fickle behaviour of the citizens and remind them that not that long ago they were enthusiastic in their support of Pompey. Their anger and strong rebukes send the citizens silently and guiltily on their way.

The scene demonstrates to the audience the ease with which Rome's citizens can be made to shift their loyalties. It ends with Marullus and Flavius leaving to tear down decorations put up in Caesar's honour after expressing their fear that Caesar is growing too powerful.

Scene ii

In Shakespeare's day many scenes flowed seamlessly from one to the next. This scene begins with Caesar and his entourage walking onto the stage while the tribunes from the previous scene are walking off. Caesar is on his way to the celebrations for the holiday Lupercalia (traditionally held on 15 February, a celebration when young men would run through the city hitting people with thongs of goatskin).

Travelling with Caesar are his wife, Calphurnia, Mark Antony (who is racing as part of the celebrations today), Brutus, Cassius, Casca and several other characters. Caesar tells his wife to stand in Antony's way as he runs and tells Antony to make sure he hits her. This is because it is believed women would be cured of infertility in this way. In this way Shakespeare reveals Caesar's desire to have children and hints that his ambition may be to secure a lasting monarchy for his family.

As the group continue on their way a soothsayer calls out to Caesar and tells him to beware the Ides of March (the dividing point of the month, in March this is the fifteenth). After he calls the soothsayer closer so he can look at him, he dismisses the warning as the words of a dreamer. It is interesting to note Shakespeare's contrast of Caesar's superstition when it comes to his wife's fertility and his lack of superstition at the soothsayer's warning.

Caesar's group continues on to the celebrations but Cassius and Brutus stay behind. Cassius carefully begins to try and convince Brutus to join him in a plot to kill Caesar. He starts by flattering Brutus and telling him that all of Rome thinks highly of his noble character. When a shout from the gathered crowds surprises Brutus, he wonders if the crowd has proclaimed Caesar their king. Cassius seizes on this opportunity and tells Brutus about several occasions on which he has witnessed Caesar's weakness.

The moments of weakness that Cassius describes are actually moments of physical weakness but Cassius describes them as symptoms of Caesar's moral weakness and unsuitability for leadership. Brutus doesn't seem to notice Cassius' petty description.

A second shout is heard from the crowd and Brutus becomes even more convinced that Caesar is being honoured in some way. Cassius takes the opportunity to remind Brutus of his ancestor Lucius Junius Brutus who helped to overthrow Tarquin and establish the Republic. Brutus agrees to think about the things Cassius has said as Caesar and his entourage enter the scene again.

Caesar appears to be unhappy and comments on the way that Cassius looks lean and hungry, saying that he is a dangerous man. As the group leaves, Casca falls behind and tells Brutus and Cassius what happened with the crowd.

Casca tells them that three times Antony offered a crown to Caesar and three times Caesar refused it. The crowd that Brutus could hear shouting wasn't calling for Caesar to accept it, but rather were cheering his refusal of it.

On the surface this action appears to endorse the idea of a noble Caesar who is committed to Rome, but Casca explains that in his opinion Caesar really did want the crown. It looks like the event may have been staged to test whether or not the citizens would tolerate or even welcome Caesar as their king. This is another hint of Caesar's ambition.

Casca then mentions that after refusing the crown three times, Caesar fell down and foamed at the mouth in some sort of fit. Before this happened, though, Caesar had offered the crowd his throat to cut after realising they were happy that he refused the crown. Casca tells them he wanted to take Caesar up on this offer, but he wasn't able to.

Once his story is done Casca is invited to dinner with Cassius and both Casca and Brutus go their separate ways. When he is alone Cassius reveals his plans to deceive Brutus with fake notes from citizens that will help him to get Brutus to join his conspiracy.

Scene iii

This scene begins with the crashes of thunder and lightning as a storm rages around the city. This is meant to increase the tension and reflects the Elizabethan and Roman beliefs that a storm can be an omen of trouble ahead. Casca enters from one side of the stage with his sword drawn. Cicero enters from the other side and greets Casca.

Casca speaks to Cicero about his fears that the storm may be an omen for terrible things about to happen. Cicero isn't convinced and goes on his way home. Cassius then enters and is excited by the storm, telling Casca that he has walked through it ‘unbraced', baring himself to the storm.

When Casca questions the wisdom of Cassius' behaviour, Cassius responds by telling him that the unnatural night reflects the presence of a man in Rome who is just as threatening. Casca identifies this unnamed man as Caesar and Cassius invites him into the conspiracy.

Cinna enters the scene looking for Cassius as other members of the conspiracy are waiting for him to meet with them. Cassius gives Cinna several letters to place where only Brutus will find them. He and Casca comment briefly on how important it is to have Brutus join their plans. The scene ends as they go to find the other conspirators then head to meet Brutus and convince him to join them.