To an Elizabethan audience, before whom Julius Caesar was first performed, the world of 44 BCE would not have seemed as remote as it might to a contemporary audience. Not only were the political struggles of early Rome relatable to seventeenth-century England, Roman and Greek history was closely known and studied. Elizabethans were also aware of the role the Roman Empire played in their history: Julius Caesar successfully invaded Britain in 54 BCE, and the Roman Empire controlled Britain from 77 to 407 CE.

Further, the political structure of Julius Caesar's Rome—with its Senate formed of 300 members of the aristocracy, the tribunes representing the poor or the plebeians, and the consuls—was not so different from Elizabethan England. The Elizabethan government was not an absolute monarchy and needed the approval of the House of Commons and the House of Lords on many important issues.

Thus, the story of Julius Caesar was an ideal template for Shakespeare to use as an allegory for his views on power and politics. Although Shakespeare does not directly criticize the monarchy in his play, he does question the idea of tyranny, which was a subtle criticism of the growing power of Elizabeth I, as well as her refusal to appoint a successor. The political uncertainty in the play mirrors not only this anxiety, but also the instability that had plagued the British monarchy, with its frequent overthrows and complex battles over succession, throughout British history. In the play, the reader can almost sense an underlying clamor for peace and certainty; however, Shakespeare’s realistic worldview keeps him from easy resolutions. Though Caesar is assassinated and the threat of tyranny warded off, the people of Rome do not achieve any measure of stability. Cynically, Shakespeare depicts the Roman mob as mindless, critiquing the lack of political and self-awareness among most people. The Roman mob slyly represents the worst of the Elizabethans and, in fact, any audience, moved first by Brutus and then by Antony. The audience’s changing reactions offer a meta-commentary on the fickle, easily moved nature of crowds.

The chaos and uncertainty pervading the plot are amplified by the imagery and use of the supernatural. Blood, fire, and animals are some of the chief elements of the play’s imagery, all three representing tame and wild aspects. When blood is inside the body, it is a symbol of nurture, valor, and constancy, such as Brutus telling Portia:

You are my true and honorable wife,
As dear to me as are the ruddy drops
That visit my sad heart.

However, shed outside the body, blood becomes symbolic of violent change. In act 3, the hands of Caesar's assassins “smoke” purple with his blood, while Antony berates himself to Caesar’s corpse for “shaking the bloody fingers of thy foes.” Antony’s speech in act 3 refers to Caesar’s blood repeatedly, describing his wounds as red mouths and using blood to tell the story of Caesar’s murder.

Through this the well-belovèd Brutus stabbed.
And as he plucked his cursèd steel away,
Mark how the blood of Caesar followed it,
As rushing out of doors, to be resolved
If Brutus so unkindly knocked, or no.

The effects of the blood imagery are multilayered: when Antony describes the blood “streaming” from Caesar’s wounds, the audience can visualize the visceral horrors of the death. The bleeding body of Caesar would also be code for the bleeding Christ for an Elizabethan audience, stirring their emotions.

Fire often accompanies bloodshed in the play, as if an act of vengeance and purification. Right after Antony’s speech, the incensed mob goes off to “burn” the houses of the traitors. Later in the play, Brutus’s wife, Portia, kills herself by “swallowing fire,” as if as a sacrifice for Caesar’s blood. Fire is also a symbol of the supernatural: on the eve of the Ides of March, the very heavens seem on fire with lightning. Like blood, fire when contained can be an illuminating taper or the fire of the forge, in which one’s metal/mettle is tempered. Released from its natural state, it manifests as violence and supernatural omens, such as a man who walks the streets unhurt though his hand blazes with fire. Animal imagery operates along a similar axis. In check, human nature is “base spaniel fawning,” indicating a demeaning, dog-like devotion. Unchecked, it is hellish, like the “dogs of war.” The portents of lions walking the streets foreshadow the end of Caesar, the lion among men, who is displaced from his natural state into strange environments.

Though portents in the play most commonly occur in conjunction with Caesar, Calpurnia’s remark that the heavens are indifferent to commoners but announce the deaths of kings is not completely true. Cassius is not a king, yet his death is foretold toward the end of the play. Why is his death foretold? The play does not provide clear answers. Possibly the omens are effective storytelling devices, foreshadowing the play’s later events as well as introducing a dark, ominous atmosphere into the proceedings. The portents are often unnatural or gruesome, such as a “bird of night,” or an owl, shrieking at midday.

Beginning with the portents, the supernatural intensifies over the course of the play to culminate in the form of Caesar’s ghost. The appearance of Caesar's phantom can be read as both an omen and a projection of Brutus’s troubled psyche. Ghosts were a frequent device in Elizabethan tragedy in general and Shakespeare’s plays in particular. However, the supernatural elements in Julius Caesar work particularly well because they mirror the psychological horror and anxiety of Shakespeare, his characters, and his audience.