Downfall of an Empire

An empire involves the extension of a state's sovereignty over external territories. The greatness of an empire is based on the extent, population, economy, duration and many other factors such as type of rule and government, satisfaction by its people etc. The calculation of the land area of a particular empire is controversial. In general, the sequence in list centers on all the aspects that make an empire mighty, strong and progressive and all the factors as mentioned that make a kingdom great.