Late Roman Republic, Gaius Pompeius Magnus (fl.82-48 BC): Third Mithridatic War (74-63 BC)

On his death Nicomedes IV of Bithynia (r.c.94-75/4 BC), following the examples of Attalus III of Pergamum (133 BC) and Ptolemy Apion of Cyrene (96 BC), bequeathed his kingdom to Rome. In spring 74 BC Bithynia was declared a Roman province. Mithridates VI, unwilling to see control of the entrance to the Black Sea in Roman hands, declared war on Rome, sent troops into Cappadocia, Paphlagonia and Bithynia, and dispatched envoys to Spain to negotiate a treaty with Sertorius. 

To cement a treaty Sertorius sent Marius (5) (=Varius?), to Mithridates and the king appointed him to replace Archelaus who had defected to Sulla. The consul ⁰⁶Aurelius Cotta was dispatched to the new province, while his colleague ¹²Licinius Lucullus obtained the overall command of the war and contrived to have Cilicia (west) and Asia assigned to himself.

Cotta’s orders were to hold Mithridates in check in Bithynia and with a fleet collected from the allies to close the Bosporus to Mithridates’ navy. Lucullus, meanwhile, was to add the veteran legions of ¹³Servilius Vatia and ⁰³Flavius Fimbria in Asia to the fresh legion he was bringing with him and advance through Phrygia against Mithridates’ flank.

In spring 73 BC, Cotta sailed to the Bosporus but was defeated off Chalcedon, on the Asian shore across from Byzantium. His admiral ⁰³Rutilius Nudus took command of the land forces but was defeated outside the Chalcedon by the advancing army of Mithridates. Cotta and his men sought refuge in the city. The Pontic ships forced their way into the harbour of Chalcedon, burned four of sixty-odd Roman ships anchored there and towed away most of the rest.