Changes

==The Rise of Sassanian Persia==

In 224 AD, Ardashir, the ruler of Fars in modern Iran, defeated and killed the last of the Parthian kings and this is seen as the beginning of the Sassanian Empire. Its Emperors or ‘King of Kings’ portrayed themselves as the heirs of the Great Persian Empire of Xerxes <ref> Heckster, p 139</ref>. It was a much more formidable state that the Parthian and within two decades, the Sassanians ruled an area much larger than anything governed by their predecessors. The neo-Persian Empire was a centralized state and had a regular army. From the 220s it began raiding Roman Syria and Asia Minor under the capable and ruthless Shapur I. The emergence of a new power in the east was a very serious challenge for the legions. It seemed that the army was overstretched as they were forced to fight Germans in Europe and Persians in the Near East. In consequence, the legions could not defend the frontiers. This, in turn, led to the rise of local warlords and ultimately the rise of the Palmyrene Empire, which for a time ruled almost all of the near East and even Egypt. The foundation of the Sassanian Empire, under a series of able rulers, was one of the most significant factors in the Third Century Crisis.

==Natural Calamities==

The inability of the Romans to defend their borders was related to socio-economic factors. A pandemic had decimated the Imperial territories in the 250s and 260s and this led to population decline. The plague according to Gibbon, ‘five thousand persons died daily in Rome, and many towns, that had escaped the hands of the barbarians, were entirely depopulated’ <ref>Gibbon, I, chapter 8</ref>. This had serious repercussions as the army found it harder to recruit legionnaires and the tax base was much reduced, which led to serious economic dislocation. Then as we have seen climate change reduced the yield of agricultural surplus and this led to the near collapse of long-distance trade. Then the constant tax demands of the Emperors added to the dire situation in many provinces. All of these compounded the difficulties facing Rome and weakened its ability to defend itself against the Persians and Germans. However, the economic and social decline of the Empire should not be overstated, as seen in its revival under the Illyrian Emperors.