It is commonly assumed that Indigenous nations had neither sovereignty in international law nor title to their territories when Europeans first arrived in North America. Thus the continent was legally vacant and European powers could gain title to it simply by such acts as discovery, symbolic acts, or occupation, or by concluding treaties among themselves. This paper argues that this viewpoint is misguided and cannot be justified either by reference to positive international law or to basic principles of justice. To (...) the contrary, Indigenous American nations were sovereign entities holding exclusive title to their territories at the time of European contact, and they participated actively in the formation of Canada and the United States. This fact requires us to rewrite our constitutional histories and reconsider the current status of Indigenous nations. (shrink)