Theory of imperialism in the context of Ultra-imperialism

Theories of imperialism offer a range of theoretical approaches to understanding (for example) the expansion of capitalism into new areas, the unequal development of different countries, and economic systems that may lead to the dominance of some countries over others. These theories are considered distinct from other uses of the word "imperialism" which refer to the general tendency for empires throughout history to seek power and territorial expansion. While some theories of imperialism were developed by non-Marxists, other theories stem from Marxist economics. Many theories of imperialism, with the notable exception of ultra-imperialism, hold that imperialist exploitation leads to warfare, colonization, and international inequality.