What caused Classical Empires to decline, collapse, or transform into something else?

The decline and collapse of classical empires was often the result of a combination of factors. These included internal and external conflicts, economic challenges, and changing political structures. Internally, deficiencies in the governing systems and civil wars between powerful rulers weakened the structure and ability of empires to maintain their power. Externally, invasions from other nations, as well as natural disasters, could disrupt an empire and cause its decline. Additionally, advances in technology and economics led to changes in political structures and altered the balance of power between nations, which could lead to transformations or collapses of empires. Lastly, environmental or climatic changes, such as droughts, floods, and crop failures, could place an additional strain on economies and political systems, which would contribute to the decline of an empire.

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