Upper-class men of Shakespeare's time were often educated in Greek and Latin, and Macbeth contains several allusions to Roman history that this portion of his audience would have appreciated. In Act 2, Scene 1, Macbeth makes a reference to an event that catalyzed the creation of the Roman Republic:

Macbeth: [A]nd withered murder,
Alarumed by his sentinel, the wolf,
Whose howl’s his watch, thus with his stealthy pace,
With Tarquin’s ravishing strides

Lucius Tarquinius Superbus, also known as Tarquin the Proud, became king of Rome in 534 BCE after assassinating his predecessor, Servius Tullius. Like Macbeth, he did so at the urging of his wife and became known as a tyrannical monarch who often had his political opponents put to death.

In this passage, Macbeth is actually making a reference to Tarquin's son Sextus, who famously raped a Roman noblewoman named Lucretia in her own bed. By personifying murder as a man who walks "with Tarquin's ravishing strides," Macbeth suggests that the murder of Duncan, like the rape of Lucretia by Sextus, is an act of violation that scorns the rules of hospitality.

Macbeth's allusion to this event is also an instance of foreshadowing. Lucretia's rape and subsequent suicide so outraged the people of Rome that it led to the overthrow of Tarquin and the establishment of the Roman Republic. Like Tarquin, Macbeth is ultimately overthrown, and the ascension of Malcolm to the throne marks a change in the nature of Scottish rule characterized by a new alliance with England.

In Act 3, Scene 1, Macbeth compares himself to the Roman general Mark Antony and Banquo to Julius Caesar:

Macbeth: There is none but he
Whose being I do fear; and under him
My genius is rebuked, as it is said
Mark Antony's was by Caesar.

After Caesar was assassinated in 44 BCE, Mark Antony butted heads with Caesar's adopted son Octavian. In 31 BCE, Octavian declared war against Antony's lover, the Egyptian queen Cleopatra, and declared Antony a traitor. After his forces were defeated in battle, Antony committed suicide, and Octavian became emperor of Rome.

This passage is also a self-reference to Antony and Cleopatra, another play by Shakespeare, in which a soothsayer predicts that Mark Antony's fortunes will be less than Julius Caesar's. The Weird Sisters in Macbeth predict, in quite similar fashion, that Banquo will be both lesser and greater than Macbeth.

Both these prophecies prove true. Although Julius Caesar is assassinated, his heir becomes the emperor of Rome, while Antony is disgraced. Despite the fact that Macbeth has him murdered, Banquo's descendants still become kings of Scotland, and Macbeth dies in ignominy.

In Act 5, Scene 10, Macbeth seeks to distance himself from Antony and from other Roman generals who famously committed suicide:

Macbeth: Why should I play the Roman fool and die
On mine own sword?

Cato the Younger was a Roman senator who killed himself rather than ask for a pardon from Caesar, and Marcus Junius Brutus, the Roman statesman who famously aided in Caesar's assassination of Caesar, took his own life after being defeated by Caesar's successor. His story parallels that of Macbeth, who kills Duncan but is later defeated by forces under the command of Duncan's son. Like Brutus, who decided to die by suicide rather than live under Octavian's rule, Macbeth refuses to serve Malcolm and instead chooses to die in battle, insisting that he won't "yield / to kiss the ground before young Malcolm's feet."