The number of Sassanid combat forces in defensive and offensive approaches

Having a reliable military force is one of the necessary conditions for the formation of a stable and dynamic political system, and this need was more felt in the ancient world and in such a land like the Iranian plateau with its special geography. With the stablishment of the Sassanid Empire, the statesmen of this state tried to form a stable and numerous military forces to avoid the problems that occurred during the Arshakid period. Consequently, they could cope with the attacks of foreign states on several fronts at the same time. The main problem of this research, which has been neglected before, is the estimation of the number of defense and offensive forces of the Sassanids based on the available data. The findings of this research shows that the Sassanids got advantage from the great quantity of troops permanently and had the ability to deploy more than 100 thousand soldiers in one front. after Khosrow I’s military reforms, Sassanids having about 400 thousand permanent troops and also using the affiliated nomadic warrior forces, they employed a formidable and efficient military apparatus to defend their borders. Considering such a great quantity of troops dependent on the high economic ability of the Sassanid state. Through survey of the surviving tax data from the Sassanid kingdom shows that the Sassanids were able to pay wages to such a large force. The method of data collection in the current research is a library.