Final answer:
Pompey, also known as Pompey the Great, was a powerful politician and general in ancient Rome. He was important to the plot of the play because of his alliance with Crassus and Julius Caesar, forming the First Triumvirate.
Step-by-step explanation:
Pompey, also known as Pompey the Great, was a powerful politician and general in ancient Rome. He played a significant role in the Roman Republic during the late first century BCE. Although he is not a character in the play, Pompey is important to the plot of the play because of his alliance with Crassus and Julius Caesar, forming the First Triumvirate. This alliance sets the stage for the political tensions that eventually lead to the downfall of the Roman Republic and the rise of Julius Caesar as a dictator.