Mithridates, launching an attack at the same time as the revolt by Sertorius is sweeping through the Spanish provinces, is initially virtually unopposed.

The Senate responds by sending the consul Lucius Licinius Lucullus to Cilicia to deal with the Pontic threat.

The only other possible general for such an important command, Pompey, is in Gaul, marching to Hispania to help crush the revolt led by Sertorius.

Marcus Aurelius Cotta, having received Bithynia and Pontus as his proconsular command, had taken charge of a fleet to protect his province, having been dispatched to the east towards the end of his period as consul.

Lucullus, upon arrival in Cilicia and immediately sets forth to confront the Pontic army in Bithynia.

The original plan was that Cotta should tie down Mithridates' fleet, while Lucullus attacked by land.

Cotta had therefore been ordered to station his fleet at Chalcedon, while Lucullus marches through Phrygia with the intention of invading Pontus.

Lucullus has not advanced far when news comes through that Mithridates has made a rapid march westward, attacked Cotta, and forced him to flee behind the walls of Chalcedon.

Sixty-four Roman ships have been captured or burnt, and Cotta has lost three thousand men.

Here Cotta is forced to remain until Lucullus can to come to his rescue.