Abstract: Western Europe surpassed China in recent times both in economy and science, and the political fragmentation contributed a lot. Uniform in China and fragmentation in Europe stems from economic conditions: with highly developed agricultural production, China uniformed its vast territory and operated a huge bureaucracy system to maintain its centralization. Lacking in suitable farming technology in the rainy land, Early-Mediaeval Europe was too poor to afford bureaucracy that kept the empire uniform. The Roman Church acquired authority at that time and then precluded the unification of Europe after its economy developed. Economic conditions and religious power also explained the unification or fragmentation of other areas.