The Pre-Columbian Era was before Columbus and Europeans conquered the Natives. Scholars break this era into different stages. The lithic stage was important for the usage of new rock technologies. In the archaic period, there was mainly subsistence farming. After the archaic period, societies were more developed. There were more crafts, urban centers, military structures, and usages of metals. Examples of tribes include Eastern Woodlands culture, the Pacific Northwest Coast Indigenous peoples, the Mississippian culture (including Cahokia), Pueblo peoples and Iroquois League of Nations.