Тhe 7th c. BC is considered as the period of formation and rise of the Median Empire. Meantime, economic crises, political instability, ethnic migrations, decline in military power, foreign invasions and, eventually, collapse of ancient state structures and depopulation were observed in the Armenian Highland and in Mesopotamia in the same period. These phenomena have usually occurred in the dramatic periods of the history of ancient Near East and, as a rule, were conditioned by climate change-related problems.

KeywordsMedian Empire Iranian Plateau Assyria Urartu palaeoenvironment climate changes crisis ethnic migrations depopulation.

The fall of the Arsacid kingdom of Greater Armenia in 428 AD is generally viewed in the context of geopolitical and internal conflicts of the second half of the IV – beginning of the V centuries AD. Meanwhile, the weakening of the Arsacid throne was a result of various factors. In particular, the climatic and environmental changes documented by various palaeoclimatic and palaeoenvironmental studies indicate a comprehensive climatic phenomenon that occurred in the region around 350–450 AD, which has been named “Late Roman mega-drought” in special literature.

KeywordsKingdom of Greater Armenia Arsacid dynasty Arshak II Pap Church crisis abandonment drought climate change decline