When are empires considered to have collapsed?

Societal collapse (also known as civilizational collapse) is the fall of a complex human society characterized by the loss of cultural identity and of socioeconomic complexity, the downfall of government, and the rise of violence.[1] Possible causes of a societal collapse include natural catastrophe, war, pestilence, famine, and depopulation. A collapsed society may revert to a more primitive state, be absorbed into a stronger society, or completely disappear.

Explanation:

Often times, the biggest reason for the decline of an empire is that they have become overextended; either by reaching too far, too fast or by being forced, often times through economic need, to keep on capturing land.

Explanation:

cuban communists pressured the soviet union to place missiles in cuba.

well the fact it is basically a peninsula allowed trade to come from many places, thus allowing cultural diffusion to take place. india has seasonal monsoons that merchants travel back and forth from india using the monsoons wind patterns