A. D. Lee
This chapter explains the warfare between the Roman Empire and Sasanian Persia, specifically presenting an historical review of Roman–Persian warfare. The Roman Empire presented many new military challenges, one of the most serious and certainly the most consistent of which was that introduced by Sasanian Persia to the east. The Sasanian regime was able to pose a more serious military threat to the Roman Empire compared with its predecessor. Sasanian siege capability led to increased Roman investment in the fortification of cities and towns on and near the frontier. A recent re-examination of the evidence has prompted a revised interpretation involving Persian tunnellers deliberately collapsing their tunnel on top of Roman pursuers after a grisly underground fight in the dark.