A Roman general ignored direct Senate orders to stand down, invaded Pontus anyway, and got his army routed at the Halys River by a king he'd spent years provoking.
In 82 BC, the Roman general Lucius Licinius Murena was stationed in Asia Minor following the First Mithridatic War. Despite explicit Senate orders to stop provoking Pontus, he launched a third unauthorized raid deep into Pontic territory — apparently convinced he could finish off King Mithradates VI on his own.
Mithradates had been carefully rebuilding his forces after his defeat in the First Mithridatic War, and Murena's raids gave him the pretext he needed to fight back. At the Halys River, a small Pontic force under General Gordius held the Romans in place while the king himself arrived with his main army.
The Romans were caught off guard by the speed and scale of the Pontic response. Mithradates crossed the river and attacked. The legions — including the battle-hardened Fimbrian forces — were routed and forced to retreat in disorder. It was a significant humiliation for Rome.
Peace was eventually negotiated in 81 BC by the Roman dictator Sulla, who ordered Murena to stand down and return the territory he had seized. Murena was recalled to Rome, where he was given a triumph — a baffling honor for a general who had defied orders and lost.
The Battle of Halys was a preview of the far greater struggle to come. Mithradates VI would go on to fight Rome in three separate wars spanning decades, making him one of the most persistent and formidable adversaries the Roman Republic ever faced in the East.