The messages went out and found Tigranes already well aware of Sulla’s advance, yet very reluctant to block his progress. What was Rome doing east of the Euphrates? Of course Tigranes didn’t trust the peaceful intent, but the size of Sulla’s army did not indicate a serious Roman invasion. The important question was whether or not he should attack—like Mithridates, Tigranes feared the name, Rome, enormously. Therefore, he resolved, he would not attack until he was attacked. And in the meantime he would go with his army to meet this Roman, Lucius Cornelius Sulla.
He had heard from Mithridates, of course. A defensive and sullen letter, informing him briefly that Gordius was dead and Cappadocia once more under the thumb of the Roman puppet, King Ariobarzanes. A Roman army had come up from Cilicia and its leader (not named) had warned him to go home. For the time being, had said the King of Pontus, he had judged it prudent to abandon his plan to invade Cilicia after subduing Cappadocia once and for all. In consequence he had urged Tigranes to abandon his plan to march west into Syria and meet his father-in-law on the fertile alluvial plains of Cilicia Pedia.
Neither of the Kings had dreamed for one moment that, his mission in Cappadocia successfully completed, the Roman Lucius Cornelius Sulla would go anywhere save back to Tarsus; and by the time Tigranes believed what his spies told him—that Sulla was on the Euphrates looking for a crossing—his messages to Mithridates in Sinope had no hope of reaching their recipient before Sulla appeared on the Armenian doorstep. Therefore Tigranes had sent word of Sulla’s advent to his Parthian suzerains in Seleuceia-on-Tigris; their journey, though long, was an easy one.
The King of Armenia met Sulla on the Tigris some miles west of the site of his new capital; when Sulla arrived on the west bank, he faced the camp of Tigranes on the east bank. Compared to the Euphrates, the Tigris was a creek, running shallower and more sluggishly, brownish in color, perhaps half as wide. It rose, of course, on the wrong side of the Anti-Taurus, and received not one tenth of the tributaries the Euphrates did, nor the bulk of the melting snows and permanent springs. Almost a thousand miles to the south in the area around Babylon and Ctesiphon and Seleuceia-on-Tigris, the two rivers ran only forty miles apart; canals had been dug from the Euphrates to the Tigris to help the latter stream find its way to the Persian Sea.