Armenian host, despite odds of about more than two to one against him. This was the famous battle of Tigranocerta. It was fought on the same (pre-Julian) calendar date as the Roman disaster at Arausio 36 years earlier, the day before the Nones of October according to the reckoning of the time (or October 6), which is Julian October 16, 69 BC. Tigranes then retired to the northern regions of his kingdom to gather another army and defend his hereditary capital of Artaxata. Meanwhile, Lucullus moved off south-eastwards to the kingdom of the Kurds (Korduene) on the frontiers of the Armenian and Parthian empires. During the winter of 69–68 BC both sides opened negotiations with the Parthian king, Arsaces XVI, who was presently defending himself against a major onslaught from his rival Phraates III coming from Bactria and the far east. Battle of Artaxata In the summer of 68 BC Lucullus marched against Tigranes and crossed the Anti-Taurus range heading for the old Armenian capital Artaxata. Once again, Tigranes was provoked to attack, and in a major battle at the Aratsani River, Lucullus was defeated by the Armenian army. Soon he left this campaign, and when winter came on early in the Armenian tablelands, his troops mutinied, refusing to go further, and he was forced to withdraw southwards back into Arzenene. From there he proceeded back down through Korduene into old Assyria (Northern Mesopotamia) and in the late autumn and early winter besieged Nisibis, the main Armenian fortress city and treasury in Northern Mesopotamia. Nisibis The Armenian garrison at Nisibis was under the command of Tigranes's brother Gouras and the Greek defence expert Callimachus. At first Lucullus besieged the city to no avail; it was strongly fortified, with two walls of brick and a moat. But in the winter of 68/67 BC, during a terrible storm – when the defenders relaxed their guard – Lucullus launched a surprise attack and captured the city and its treasury. It made no difference, Mithridates and Tigranes stuck to their strategy and refused to march against Lucullus; Tigranes was in the process of taking back southern Armenia and Mithridates invaded Pontus. Mithridates return to Pontus In the spring of 67 BC, while Lucullus was laying siege to Nisibis, Mithridates suddenly returned to Pontus. The Romans had not expected Mithridates to strike at them in Pontus and he caught several small Roman detachments unaware. The