Sulla had gained greater distinction in the Marsic War than Marius, who was now verging on old age. The public eye was consequently turned to Sulla; and as, on the appearance of the Cimbric hosts twenty years before, the Romans had placed their dependence on Marius, so now, on the breaking out of war in the East, they placed their dependence on his younger rival. Mithridates VI, the young king of Pontus, an Oriental by birth, but of Greek education, and a man of splendid abilities, had been for some years silently extending his dominions in western Asia; and the Romans, long jealous of his movements, had at length openly warned him to desist. Mithridates scouted the warning; marched through Asia Minor, putting the Romans to the sword; and was welcomed everywhere by the Asiatic Greeks as a deliverer from the Roman yoke: ultimately (B. C. 88), crossing over into Greece, he menaced the Empire near its centre.
Sulla, then engaged with the Samnites, the last dregs of the Social War, was chosen consul, and invested with the command against the Eastern monarch. He was then in the forty-ninth year of his age. Vexed at the preference of his rival, the grim old Marius used all his efforts to have the appointment canceled, and himself nominated to the Mithridatic command. His political opinions recommending him to many, and a tribune named Sulpicius having procured the passing of a preliminary measure distributing the new Italian citizens among all the old tribes, which had now attained the number of thirty-five, he at length carried his point, and Sulla was superseded. But the aristocratic general was not a man to be trifled with. Marching from the south of Italy, where he was when he heard the news, he appeared with his army before the city, forced his entrance through the rotten walls, dislodged his antagonists from the houses from which they were throwing stones and missiles at his men, and compelled Marius and his adherents to save their lives by a precipitate flight. Marius escaped to Africa; Sulla, after settling affairs at Rome, set out for Greece. Here he speedily retrieved the Roman losses; sacked Athens, which had provoked him by its opposition; and reduced Archelaus, the general of Mithridates, to such extremities, that having crossed into Asia, Mithridates was glad to conclude a peace with him (B. C. 84), by which he renounced all he had gained, and agreed to pay the expenses of the war. Meanwhile a terrible reaction had occurred at Rome in Sulla’s absence. Scarcely had he left the city (B. C. 87), when Lucius Cornelius Cinna, one of the consuls whose appointment he had sanctioned, proclaimed himself on the popular side, and commenced a series of measures directly opposed to Sulla’s views. His colleague Octavius drove him from Rome, and the senate deposed him from the consulship. The Italians, however, gathered round Cinna; Marius and his fellow-exiles hearing of the movement, hastened back to Italy; all the able military men of the Marian party, and among them a young and generous commander named Sertorius, exerted themselves to raise troops; and at length the aristocratic party found themselves besieged in Rome. Famine and pestilence began their ravages in the city; and the senate, reinstating Cinna in the consulship, capitulated on the understanding that blood should not be shed. But there was little softness in the nature of Marius. Admitted into the city, the stern old man, who was already tottering on the brink of the grave, revenged his wrongs by a frightful massacre, in which many men of distinction fell. Marius then caused himself to be elected to a seventh consulship (B. C. 86), his colleague being Cinna. He enjoyed the unprecedented honor but a few days, dying on the 13th of January (B. C. 86), and Valerius Flaccus was named his successor. Flaccus, setting out with authority to supersede Sulla in the Mithridatic war, was murdered by his legate Flavius Fimbria, who assumed the command of the army, and gained some successes; but being afterwards hard pressed by Sulla, and deserted by his army, committed suicide. This occurred about the time of the conclusion of the peace with Mithridates (B. C. 84); and Sulla, after settling the affairs of Asia Minor, and draining the country of money, so remorselessly as to affect its prosperity for a century, commenced his journey homewards, with bloody purposes against Cinna and his adherents, and an army ready to execute them.