A civil war (bellum civile in Latin) is a war between citizens of the same country. During the years of the Roman Republic*, Romans fought several civil wars that were caused by rivalries between powerful generals. During the period of the Roman Empire, disputes about who would be emperor also led to civil wars.

The first civil war took place from 88 to 83 B.C. The generals Gaius Marius and Lucius Cornelius Sulla were the principal rivals. Marius had gained great popularity by persuading the Senate to grant land to the poor citizens in his army. Sulla was serving as consul* and had been appointed army commander for Rome’s possessions in the East, although he and his army were in Italy.

In 88 B.C., Mithriadates, king of Pontus in Asia Minor, invaded Rome’s eastern territories. The general who led the war against Mithridates would be in a position to acquire great wealth. Marius wanted the command and, supported by large crowds in Rome, succeeded in seizing it from Sulla. In retaliation, Sulla and his army marched on Rome, regained the command, and forced Marius to flee. While Sulla was in the East fighting Mithriadates, Marius returned to Rome and captured the city in a bloody battle. He died soon after. Sulla and his army returned to Rome in 83 B.C. and defeated Marius’s followers. Sulla executed many of his opponents and gave their land to his soldiers. He retired after ruling as dictator for several years.

The second civil war resulted in the end of the Roman Republic. The generals Pompey and Caesar and the wealthy Crassus had formed the First Triumvirate* in 60 B.C. and dominated Rome. Crassus died several years later at the Battle of Carrhae, a humiliating defeat for Rome. While Pompey ruled in Italy, Caesar conquered Gaul and invaded Britain. Soon, however, Pompey and Caesar became enemies. The wealthy classes in Rome, who controlled the Senate, tended to support Pompey. Caesar made himself the favorite of the poorer citizens.

* Roman Republic Rome during the period from 509 B.C. to 31 b.c„ when popular assemblies annually elected their governmental officials

* consul one of two chief governmental officials of Rome, chosen annually and serving for a year

* triumvirate ruling body of three

* succession transmission of authority on the death of one ruler to the next

* imperial pertaining to an emperor or empire

* dynasty succession of rulers from the same family or group

In 49 B.C., Caesar defied the Senate by taking his army into Italy and defeated Pompey in a series of battles. The decisive one was at Pharsalus in Greece in 48 B.C. Although Caesar had the smaller army, he routed Pompey, who fled to Egypt where he was killed by the Egyptian government dominated by Rome. After defeating Pompey’s allies, Caesar returned to Rome and established a dictatorship. Caesar’s dictatorship, however, was short-lived.

A group led by Brutus and Cassius, wishing to restore the republic, assassinated Caesar on the Ides of March (March 15) in 44 B.C. War then resumed between Caesar’s supporters and opponents. Two of Caesar’s followers, Marcus Antonius (Mark Antony) and Lepidus, joined with Octavian, Caesar’s adopted son, to form the Second Triumvirate. They defeated Brutus and Cassius, both of whom committed suicide, and divided the empire among themselves. The triumvirate collapsed after several years. Lepidus joined a rebellion against Octavian and was defeated. Antony had fallen in love with Cleopatra and had made an alliance with her, which resulted in his loss of support in Rome.

Octavian waged war against Antony and Cleopatra. A decisive sea battle occurred at Actium in northwest Greece in 31 B.C., which was won by Octavian’s great general Marcus Agrippa. Both Antony and Cleopatra fled to Egypt and committed suicide the following year. Octavian then had no rivals to oppose his authority, and in 27 B.C., he began his reign as Emperor Augustus.

During the Roman Empire, many civil wars occurred over succession* to the imperial* throne. Over the years, various armies would each proclaim their general as emperor, and civil war generally followed. This occurred, for example, in A.D. 69, the so-called “Year of the Four Emperors.” In that year, three generals—Galba, Otho, and Vitellius—each in turn attempted to rule as emperor after the suicide of Nero, until Vespasian finally secured the throne and restored some stability to the empire.

Another civil war occurred after the death of the emperor Pertinax in A.D. 193. The Praetorian Guard, the imperial bodyguard, made Didiusjulianus emperor. General Septimius Severus, however, marched on Rome and had the new emperor murdered. Defeating two rival generals, Severus ruled for nearly twenty years and established the Severan dynasty*, which lasted until A.D. 235. Several more civil wars occurred throughout the remaining years of the empire. (See also Rome, History of.)

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