The term “imperialism” means the process of extending one nation’s control over another; it is a process that takes many forms. Historians distinguish between “formal imperialism” and “informal imperialism.” Formal imperialism is colonialism, and it was exercised by the Europeans in the past mainly by direct rule: the colonizing nations annexed territories outright and established their own governments to subjugate and administer the peoples of these territories. Sometimes formal imperialism was exercised through indirect rule: the conquering nations reached agreements with native leaders and governed them. There was no single practice of colonial management, and resistance from the natives forced colonial powers to shift strategies frequently. As for “informal imperialism,” it refers to a more subtle and less visible exercise of power, in which the stronger nation allows the weaker one to maintain its independence while reducing its sovereignty. For the Europeans in the past, informal imperialism took the form of carving out zones of European sovereignty and privilege, such as treaty ports, within other countries. Essentially it meant using European economic, political, and cultural power to get advantageous treaties or terms of trade. Informal imperialism was not only common, it played an even more fundamental role in shaping global power relations in the 18th and 19th centuries.