While Sulla was governing Cilicia, he played a pivotal role in expressing Rome's power to its eastern provinces and rival kingdoms. Much as Marius had done earlier with Mithridates, Sulla's intimidating presence left a lasting impression. Even the powerful Parthian empire sent ambassadors to meet with him.
Sulla certainly made a lasting impression in this first major official contact between Rome and Parthia. Sulla's governorship would be largely uneventful, however, and he returned to Rome just as the political rivalry between Marius and the Senatorial Optimates was heating up.
By 89 BC, the social and political climate with Rome and Italia were at a fever pitch. The Italian allies of Rome, after years of lawful attempts to gain full citizenship, had finally had enough. The murder of their advocate, Drusus, in the Roman Senate, set off an armed conflict which would become known as the Social War. Also known as the Marsic War, as the Marsii tribe led the revolt, many Italian tribes revolted against Roman power in an attempt to either gain citizenship, or set up an exclusive state of their own.
In a war that would last 3 years, mainly because of political fighting over which factions should have command, Sulla would surpass Marius and become the most prominent general of the time. By the end of the war, Sulla for all practical purposes, was in overall command of the campaign; and his reward for victory was his election as Consul for 88 BC.
In the heart of the Social War, Mithridates VI of Pontus began stirring up trouble in the east. Looking to expand his own fledgling empire, he was directly responsible for the assassination of political rivals and invasions into neighboring Kingdoms. While Rome protested his actions, there was little that could be done while occupied with the Italians. Mithridates would eventually take control of Asia Minor, Greece, Thrace and part of Macedon while the Romans were forced to wait out there own troubles. At the close of the Social War, however, the situation came to a head when Mithridates ordered the execution of up to 80,000 Roman citizens in Asia Minor, and as many as 150,000 latin rights allies. Sulla as Consul, was appointed to take command of the effort against Mithridates, but Marius and his followers had other plans.
Sulla prepared his legions and began the march from Italy to the east. No sooner was he gone, however, than the aging Marius convinced his tribunal ally Sulpicius Rufus to put the matter of the Mithridatic command to a vote with the citizen assemblies. Still extremely popular with the commoners, Marius' desire to have the command for himself was ratified in the assemblies. Sulla was never a man to give up without a fight, though, and the ambition of both men would lead to yet more civil strife. Sulla refused to accept the political coercion of Marius and consulted with his generals on the feasibility of marching on Rome. While most of his officers resigned, rather than be a part of it, Sulla was undeterred. For the first time in history, a Roman general was about to march on Rome with legions in order to gain political power.
Sulla then broke camp and entered Rome shortly after, in 88 BC. Taking full control, he portrayed himself as the victim of Marius' intrigue against his rightful command and gave Rome a first glimpse of the future dictatorship of Sulla. He declared Marius and his followers as outlaws and enemies of the Roman state, though Marius escaped to Africa. The powers of the Tribunes were reduced and the Senate's strengthened in order to protect Roman law from the whims of the common classes. Many political rivals were hunted down and killed, but there was little time for Sulla to consolidate his power, as Mithridates waited. A new consul, L. Cornelius Cinna, was left to govern Rome, and Sulla marched back east.
No sooner had Sulla left, however, than Cinna, through political intrigue of his own, fell into disfavor with the Senate. Banished from Rome, Cinna's only choice to regain his power was to ally with Marius. With Sulla beyond reach, Marius and Cinna returned to Rome with troops of their own. Returning Sulla's favor, Cinna and Marius took control violently and the bloodbath of Roman politicians grew. Nothing before like it had ever occurred in Rome, and murder was becoming a telling pattern in Roman politics. Marius and Cinna forced through their elections as Consuls for 86 BC, but Marius, in his seventh Consulship, died just 17 days into it. Cinna was left to rule Rome ruthlessly, and would continue to rule, in the absence of Sulla, for the next three years.
Sulla, meanwhile, had to allow matters to unfold beyond his control. His primary duty was the defeat of Mithridates and the re-establishment of Roman power in the east. For now, Cinna and the Marian political faction would have to wait, but revenge would prove far deadlier than anything that had come before it.