Cicero had information that the Parthians had passed through Commagene and were in Cyrrhestica. Cassius with all of his troops was in Antioch,[1] where he was shortly afterwards surrounded by the Parthians.[2] At this time there was no news as to the whereabouts of M. Calpurnius Bibulus, governor of Syria, then on his way from Rome. Parthian patrols soon penetrated beyond the frontiers of Cilicia, and a considerable body of their cavalry was annihilated by some squadrons of Roman horse and a praetorian cohort stationed on garrison duty at Epiphanea.[3] When it became apparent that the Parthian raid was directed not toward Cappadocia but into Cilicia, Cicero proceeded by forced marches through the Taurus by the Cilician Gates and arrived at Tarsus on October 5.[4]
Both the Roman commanders and the Roman and Greek historians failed to understand the tactics employed by the Parthians. This expedition was a cavalry raid by a comparatively small force of swiftly moving horsemen whose object was not conquest, for which their numbers and equipment were inadequate, but booty and destruction of enemy property. This was the reason why they struck not at Cappadocia but at the rich area around Antioch. It was a comparatively easy matter to cross the Euphrates, avoid
