Early in his career, Mithridates allied with his neighbor King Nicomedes III of Bithynia to divvy up territory in Anatolia. Roman ambassadors ordered them to desist, but with Roman attention tied up with Jugurtha and the Cimbri, there was little the Romans could do. Eventually, Mithridates and Nicomedes had a falling out over control of Cappadocia, which bordered both kingdoms and served as the overland trade link between the Black Sea and the Mediterranean. In 101, Mithridates personally slit the throat of the king of Cappadocia and placed his own son on the throne. This was the settlement Mithridates wanted ratified when his ambassadors were abused in Rome by Saturninus.5
With Mithridates now commanding an international reputation, Gaius Marius made a point to meet the Pontic king on his circuit of the east in 98. After a conference, Marius told Mithridates, “Either strive to be stronger than Rome, or do her bidding without a word.” Some say Marius already had his eye on a future war with Mithridates, but for the moment Pontus was just another random eastern kingdom. There was no reason for Marius to suspect what would become obvious a decade later: that Mithridates VI was not just Mithridates VI—he was Mithridates
A few years later, Mithridates’s ambitions provoked the Senate to intervene in Cappadocia when they ordered Sulla to place the client king Ariobarzanes on the throne. But despite this minor setback, Mithridates recovered. Not only did he secure a marriage alliance with the powerful King Tigranes I of Armenia, but his old rival Nicomedes III died in 94 leaving a mere boy on the Bithynian throne. With the Romans mired in the Social War, Mithridates induced Tigranes to invade Cappadocia while he invaded Bithynia. Both the puppet king Ariobarzanes and the boy king Nicomedes IV fled to Rome.7
THE REFUGEE KINGS of Cappadocia and Bithynia arrived in Rome just as the Social War was breaking out. The Senate had more important things to worry about than who controlled a few dusty goat paths in Anatolia, so they ignored the entreaties of the two young kings. To gin up interest in their plight, the kings promised lavish indemnities in exchange for help, so the Senate relented and sent an embassy to escort Nicomedes and Ariobarzanes back across the Aegean. The man they selected for the job was Manius Aquillius, Marius’s former lieutenant and victor of the Second Servile War.8
When the Romans arrived, Mithridates and Tigranes withdrew back to their own kingdoms rather than tangle with the Romans. Reinstalling the two kings, Aquillius leaned heavily on them to make good on the lavish promises they had made back in Rome. The kings sputtered about poverty, but Aquillius told them all wealth they ever needed was in Pontus for the taking. A charitable reading of Aquillius pushing the kings to invade Pontus is that he believed Mithridates an empty shirt. So far any time the Roman gaze turned to him, the Pontic king averted his eyes and retreated to his den. But it has also been suggested that as a close friend and ally of Marius, Aquillius was deliberately provoking Mithridates so Marius could lead the eastern command he coveted. Of course, it’s also possible Aquillius was just being stupid.9
In the spring of 89, Nicomedes IV invaded Pontus. But Mithridates was not an empty shirt, and the Pontic army sent the Bithynians limping home in a broken heap. Mithridates complained to Aquillius about the encroachment, but got no response. So the king concluded that Rome planned to use its client kingdoms to squeeze Pontus off the map. But Mithridates had no intention of being squeezed off the map. After years of careful groundwork, the king of Pontus was ready to reveal the full potential of his Black Sea empire.10
To get Aquillius’s attention, Mithridates sent armies into Cappadocia and once again chased Ariobarzanes out of the country. Then he fortified the frontier with Bithynia and sent an embassy to Aquillius in Pergamum. These ambassadors read aloud a list of all Mithridates’s foreign alliances, and gave a full accounting of the resources at his disposal—from the size of his treasury, to the number of men he could conscript, to the number of ships in his fleet. The ambassadors then said that if Rome was not careful they risked losing their dominions in Asia. It was not a declaration of war. But it was an invitation for a declaration of war.11
