Most efforts to explain imperialism turn to European expansion in the modern era as their model. But none of these explanations seem relevant to Mongol imperialism. In fact, they appear contradicted by the Mongol example. During the era of modern European empires, imperialism usually was attributed to one of two factors: either the expansive vigor of the European capitalist economy or the humanitarian virtues of European culture, embodied either in the Christian religion or secular reason. Capitalism played no role in Mongol imperialism; neither did any desire by the Mongols to spread their beliefs or customs to other peoples. Underwriting European explanations of their imperial success was the conviction that human history was a story of progress form hunter and herder to agrarian and industrial societies. It made little sense in terms of this model that a herder peoples like the Mongols could overcome more sophisticated agrarian societies, whose presumed superiority was confirmed by the label ‘civilizations’. Even though modern theories of imperialism are much more critical of its effects, they remain at least implicitly wedded to many of the same assumptions about its relationship to modernity. European imperial domination is attributed in one way or another to factors that made it more ‘modern’ and ‘advanced’ than the societies it conquered. Thus, attention has focused on capitalism and trade, the nation-state and nationalist rivalries, science and industrial technology, and so forth. None of these factors offer a basis for explaining the Mongol case. This fact obliges us to appreciate more fully the limitations of the theories we construct to explain general phenomena like imperialism.