Gaius Marius was a successful general and lawmaker in the days of the Roman Republic. Known as the "third Founder of Rome" for his victory against a barbarian coalition, he is also known for a bloody campaign of political retribution carried out late in his career.

He was born about 157 B.C. in Arpinum, Italy. He was born not into a rich family and so was a plebeian; his family probably did not have a lot of money or access to an education for him.

He started his political career as quaestor and praetor and then was elected tribune to the plebeians. In 115 B.C., he won the governorship of Farther Spain. After marrying into a wealthy family, to a woman named Julia, he won election as a consul a record seven times, the first coming in 107 B.C.

His first consulship came in the midst of a war against the Numidian king Jugurtha. Marius originally served under Consul Quintus Caecilius Metellus but, after concluding that Metellus was the wrong commander for the job, returned to Rome and got himself elected consul and then named himself head of the army. He returned to Africa and had resounding success, ending that threat in 105 B.C. His influence on the Roman army was marked. In the face of invasions by various "barbarian" tribes, he increased membership in the army by providing funds to pay and equip them; this overcame for many the burden of financing armor and weapons. The one sour note for Marius in the victory of Jugurtha was that another commander negotiated Jugurtha's surrender. That commander was Lucius Cornelius Sulla Felix, known as Sulla, who saw an opportunity to make a name for himself and took it, much like Marius had in coming to Africa to fight Jugurtha. Sulla's taking a responsibility that by rights should have belonged Marius created an enmity between the two men.

The very next year, Rome faced a dire threat in the Cimbri, a barbarian tribe who seemed to have Rome's number. In desperation, the Romans re-elected Marius as consul, a clear violation of established law, which required a 10-year waiting period before a person could again serve as consul. The Romans, confident that Marius's generalship was worth it, agreed. They were so confident in his abilities and so confident that they were right in naming him consul in order to save Rome from invasion that they elected him a few more times while the looked-for Cimbri invasion remained a mirage. Finally, however, the barbarians were ready to rampage.

The Cimbri had gained an ally in the Teutones, and the two armies planned to hit Rome from both north and south at the same time. Anticipating this, Marius moved quickly and checked the Teutone advance at Aquae Sextiae in 102 B.C. Despite the sudden appearance of another army, that of the Ambrones, Marius and the Romans were successful. Marius turned his full firepower on the Cimbri and scored a knockout blow at Vercellae in 101 B.C., resulting in 60,000 Cimbri dead and many, many captured. For the entire war, the Romans claimed a figure of enemy dead of 360,000 and of enemy captured of 150,000. After this momentous victory over the Cimbri and their allies, the Roman people dubbed Marius the "third founder of Rome" (after Romulus and Camillus.

Having already waived the 10-year waiting period between consulships, the people kept electing Marius as consul. He served his fifth consecutive term at the top of the political ladder.

Another way in which Marius reformed the army was to do away with a large number of the pack animals that served the purpose of carrying the soldiers' supplies but also slowed down the pace at which the army could travel without losing control of its supplies. By requiring soldiers to carry their own supplies, Marius made initial enemies of his soldiers, as some of them struggled to carry the extra weight; however, the new speed capability of the legions gave them a mobility that proved invaluable in future struggles.

Marius took a turn for the corrupt for his sixth consulship, bribing enough people to ensure his election as consul and throwing in his lot a group of politicians who had no qualms about committing unscrupulous acts. Marius left the consulship and served as a Senator for several years.

Pressed back into duty during the Social War of 91 B.C., Marius led troops into victory against Rome's Italian allies, who had had enough of Roman hegemony. Whether through his own bouts with illness or his struggles against political enemies, he retired from the campaign after a year of fighting. The last remaining foe was King Mithridates VI of Pontus. Marius wanted to come out of retirement and lead the legions of Rome against this new threat; however, Sulla, Marius's former deputy, got himself named as commander and set off to do battle with Mithridates and his army.

Marius insisted on taking the command and talked the tribune Sulpicius into convincing the Roman people to take the command away from Sulla and give it to Marius. An enraged Sulla returned to Rome at the head of the army and forced Marius to flee. Just to make sure that that sort of thing didn't happen again, Sulla, who had taken control of the government, declared Marius an enemy of the state and ordered him to be found and executed.

Marius hit out in the hinterlands for a few years, even going to Africa at one stage, there to raise an army to lead back to Rome. He did so in 87 B.C., when the two consuls, Cinna and Octavius, were at each other's throats. Marius returned and threw in his lot with Cinna; that combination was enough to oust Octavius, and Cinna and Marius then ruled Rome.

The pair set about dispatching their political enemies, without so much as a trial to examine whatever charges they faced. Deaths numbered in the dozens. In 87 B.C., Cinna and Marius were re-elected consul; this was Marius's seventh term in the post. The following year, he died of illness; he was 71.