A mob of Roman plebeians is on the point of rioting over the shortage of grain, which they accuse the patricians, their rulers, of hoarding. Menenius Agrippa, a good-natured member of the patrician class who is popular with the plebeians, attempts to pacify them. But he is soon joined by his friend Caius Marcius, who detests the common people and treats them with contempt. The people grow angry, but they are interrupted by a messenger who comes to tell Caius Marcius that the Volscians, enemies of the Romans, have put an army in the field, and so he must prepare for battle.

While the senior general, Cominius, meets the Volscian army in battle, Caius Marcius is tasked with capturing the city of Corioli. He does so, fighting heroically, and then immediately rides to the aid of Cominius and his troops, who are in retreat. The reinforced Roman army attacks the Volscians again and this time defeats them, with Caius Marcius fighting courageously. He encounters his sworn enemy, the Volscian general Tullus Aufidius, in the field, but some of the Volscian troops rescue Aufidius and drag him away from the battle, to his grave chagrin. Cominius honors Caius Marcius with the agnomen, or title, of Coriolanus, to commemorate his capture of Corioli.

In Rome, Caius Marcius, now called Coriolanus, has achieved such heroic status that the patricians, and even many of the plebeians, cry out for him to be elected consul. His selection by the senate is a mere formality, but he cannot bring himself to be polite to the plebeian delegates who must confirm his appointment. The plebeians are going to select him as consul despite his insults, but they are stirred to anger by the two tribunes, Sicinius Velutus and Junius Brutus, who hate and fear Coriolanus. When the plebeians change their minds about accepting Coriolanus, he furiously denounces the tribunes and says they should be stripped of their powers, since plebeians should not wield such power over patricians.

Sicinius Velutus and Junius Brutus say that Coriolanus’s words amount to treason, and they demand that he be executed in the traditional manner: by being hurled from the top of the Tarpeian Rock. Coriolanus’s friends, Menenius and Cominius, and even his formidable mother, Volumnia, exhort him to speak mildly to the tribunes and make peace. Coriolanus cannot bring himself to do so, and once again he addresses both tribunes and plebeians with bitter contempt. He is not executed, but he is banished from Rome. He embraces his fate, saying, “There is a world elsewhere.”

After the fall of Corioli to the Romans, the Volscian general, Tullus Aufidius, has retired to the city of Antium. Coriolanus goes there and enters Aufidius’s house. He says that the Volscian can cut his throat if he wishes. If he chooses not to do so, however, Coriolanus will serve him and help him to conquer Rome. Aufidius instantly abandons his personal enmity and hails Coriolanus as a friend. Together, they put an army on the field.

The Volscians set up camp close to Rome, ready to attack the city. The Romans send Coriolanus’s two closest friends, Cominius and Menenius, to reason with him, but he will not listen to either of them. Finally, they send an embassy of women, including Volumnia, Coriolanus’s mother, and Virgilia, his wife. Volumnia points out that Coriolanus need not turn against the Volscians and fight for Rome again. He can negotiate a peace treaty between the two sides. Moved by his mother’s appeals, Coriolanus agrees to do this, taking no notice of Aufidius, who is infuriated by this...