The death of Gaius brought little peace, and trouble came from two sources: the outbreak of new wars in the Mediterranean basin and further political unrest in Rome. In 112 B.C.E., Rome declared war against the rebellious Jugurtha (joo-GUHR-thuh), king of Numidia in North Africa. Numidia had been one of Rome’s client kingdoms, a kingdom still ruled by its own king but subject to Rome.

The Roman legions made little headway against Jugurtha until 107 B.C.E., when Gaius Marius (MEHR-ee-uhs), a politician not from the traditional Roman aristocracy, became consul and led troops to Numidia. Marius was unable to defeat Jugurtha directly, but his assistant, Sulla, bribed Jugurtha’s father-in-law to betray him, and Jugurtha was captured and later executed in Rome. Marius later claimed this as a victory.

Fighting was also a problem on Rome’s northern border, where two German peoples, the Cimbri and Teutones, were moving into Gaul and later into northern Italy. After the Germans had defeated Roman armies sent to repel them, the Senate sent Marius to lead the campaign against them. Before engaging the Germans, Marius encouraged enlistments by promising volunteers land after the war. Poor and landless citizens flocked to him. Marius and his army conquered the Germans, but when Marius proposed a bill to grant land to his troops once they had retired from military service, the Senate refused to act. It was a disastrous mistake. Henceforth the legionaries expected their commanders—not the Senate or the state—to protect their interests.

Rome was dividing into two political factions, both of whom wanted political power. The populares attempted to increase their power through the plebeian assembly and the power of the tribunes, while the optimates employed the traditional means of patron-client relationships and working primarily through the Senate. Both of these factions were represented in the Senate, and both had their favored general. Marius was the general backed by the populares, while the favored general of the optimates was Sulla.

In 90 B.C.E., many Roman allies in the Italian peninsula rose up against Rome because they were expected to pay taxes and serve in the army, but they had no voice in political decisions because they were not full citizens. This revolt became known as the Social War. Sulla’s armies gained a number of victories over the Italian allies, and Sulla gained prestige through his success in fighting them. In the end, however, the Senate agreed to give many allies Roman citizenship in order to end the fighting.

Sulla’s military victories led to his election as consul in 88 B.C.E., and he was given command of the Roman army in a campaign against Mithradates, the king of a state that had gained power and territory in what is now northern Turkey and was expanding into Greece. Before he could depart, however, the populares gained the upper hand in the assembly, revoked his consulship, and made Marius the commander of the troops against Mithradates. Riots broke out. Sulla fled the city and returned at the head of an army, an unprecedented move by a Roman general. He quelled the riots, put down his opponents, made some political changes that reduced the power of the assembly, and left again, this time to fight Mithradates.

Sulla’s forces were relatively successful against Mithradates, but meanwhile Marius led his own troops into Rome in 86 B.C.E., undid Sulla’s changes, and killed many of his supporters. Although Marius died shortly after his return to power, the populares who supported him continued to hold Rome. Sulla returned in 83 B.C.E., and after a brief but intense civil war he entered Rome and ordered a ruthless butchery of his opponents. He then returned all power to the Senate and restored the conservative constitution as it had been before the Gracchian reforms. In 81 B.C.E., he was granted the office of dictator, a position he used to enhance his personal power. Dictators were supposed to step down after six months—and many had done so in Roman history—but Sulla held this position for two years. In 79 B.C.E., Sulla abdicated his dictatorship because he was ill and believed his policies would last. Yet civil war was to be the constant lot of Rome for the next forty-eight years, and Sulla’s abuse of political office became the blueprint for later leaders.